Pipeline reinstatement tool

ABSTRACT

A new, innovative tool useful in fluidly coupling a lateral pipeline to a reinstated pipeline containing a continuous liner is provided. The pipeline reinstatement tool includes a flexible shaft that is coupled to a cutting head at a first end and a coupling assembly at a second end. The cutting head includes a hollow cylindrical member having cutting teeth that project longitudinally from the first end of the hollow cylindrical member. The tool includes a first compressible tensioner portion disposed about the flexible shaft proximate cutting head, a second compressible tensioner portion disposed about the flexible shaft proximate the coupling assembly, and a flexible sleeve portion disposed about the flexible shaft between the first compressible tensioner portion and the second compressible tensioner portion.

TECHNICAL FIELD

The present disclosure relates to tools used to reinstate pipelines.

BACKGROUND

As pipelines age and deteriorate, few options exist other thanreplacement, which can be disruptive, financially costly, and timeconsuming, or restoration by installing a liner material that can becured in place and doesn't require pipeline replacement. Typically, suchin pipeline restorations or reinstatements the pipeline is first cleanedand a flexible liner is installed and cured in place. For example, aflexible fabric or fiberglass tube may be impregnated with a chemicallyor electromagnetically curable resin. The flexible tube is routedthrough the deteriorated pipeline and expanded to provide a full-bore ornear full-bore passage. The resin is then cured, providing a seamless,rigid, lining system that extends the length of the pipeline. Afterinstalling and curing of the liner, holes are made in the liner at eachlateral connection to permit flow from the lateral connection into thereinstated pipeline.

BRIEF DESCRIPTION OF THE DRAWINGS

Features and advantages of various embodiments of the claimed subjectmatter will become apparent as the following Detailed Descriptionproceeds, and upon reference to the Drawings, wherein like numeralsdesignate like parts, and in which:

FIG. 1 is a block diagram depicting an illustrative pipelinereinstatement tool that includes a flexible shaft, a cutting headaffixed to a first end of the flexible shaft, a first flexible sleevehaving a first axial length (L₁), a compressible tensioner, a secondflexible sleeve having a second axial length (L₂), and a couplingassembly that couples a second end of the flexible shaft to a rotatableexternal drive shaft, in accordance with at least one embodimentdescribed herein;

FIG. 2A is an plan view of an illustrative pipeline reinstatement toolthat includes a flexible shaft having a first end and a second end, acutting head affixed to the first end of the flexible shaft, a firstflexible sleeve, a second flexible sleeve, a compressible tensionerdisposed between the first flexible sleeve and the second flexiblesleeve, and a coupling assembly disposed proximate the second end of theflexible shaft, in accordance with at least one embodiment describedherein;

FIG. 2B is a cross-sectional elevation of the illustrative pipelinereinstatement tool depicted in FIG. 2A along sectional line 2B, inaccordance with at least one embodiment described herein;

FIG. 2C is a cross-sectional elevation of the illustrative pipelinereinstatement tool depicted in FIG. 2A along sectional line 2C, inaccordance with at least one embodiment described herein;

FIG. 2D is a cross-sectional elevation of the illustrative pipelinereinstatement tool depicted in FIG. 2A along sectional line 2D, inaccordance with at least one embodiment described herein;

FIG. 2E is a cross-sectional elevation of the illustrative pipelinereinstatement tool depicted in FIG. 2A along sectional line 2E, inaccordance with at least one embodiment described herein;

FIG. 2F is a cross-sectional elevation of the illustrative pipelinereinstatement tool depicted in FIG. 2A along sectional line 2F, inaccordance with at least one embodiment described herein;

FIG. 2G is a cross-sectional elevation of the illustrative pipelinereinstatement tool depicted in FIG. 2A along sectional line 2G, inaccordance with at least one embodiment described herein;

FIG. 2H is a cross-sectional elevation of the illustrative pipelinereinstatement tool depicted in FIG. 2A along sectional line 2H, inaccordance with at least one embodiment described herein;

FIG. 2I is a cross-sectional elevation of the illustrative pipelinereinstatement tool depicted in FIG. 2A along sectional line 2I, inaccordance with at least one embodiment described herein;

FIG. 2J is a cross-sectional elevation of the illustrative pipelinereinstatement tool depicted in FIG. 2A along sectional line 2J, inaccordance with at least one embodiment described herein;

FIG. 3A is an plan view of an illustrative pipeline reinstatement toolthat includes a flexible shaft having a first end and a second end, acutting head affixed to the first end of the flexible shaft, a sleeve atleast partially covering the cutting head, a first flexible sleeve, asecond flexible sleeve, a compressible tensioner disposed between thefirst flexible sleeve and the second flexible sleeve, and a couplingassembly disposed proximate the second end of the flexible shaft, inaccordance with at least one embodiment described herein;

FIG. 3B is a cross-sectional elevation of the illustrative pipelinereinstatement tool depicted in FIG. 3A along sectional line 3B, inaccordance with at least one embodiment described herein;

FIG. 3C is a cross-sectional elevation of the illustrative pipelinereinstatement tool depicted in FIG. 3A along sectional line 3C, inaccordance with at least one embodiment described herein;

FIG. 4A is an plan view of an illustrative pipeline reinstatement toolthat includes a flexible shaft having a first end and a second end, acutting head affixed to the first end of the flexible shaft, a pluralityof resilient members disposed about the cutting head, a hemisphericalfloating spacer element a first flexible sleeve, a second flexiblesleeve, a spherical floating spacer element, a compressible tensionerdisposed between the first flexible sleeve and the second flexiblesleeve, and a coupling assembly disposed proximate the second end of theflexible shaft, in accordance with at least one embodiment describedherein;

FIG. 4B is a cross-sectional elevation of the illustrative pipelinereinstatement tool depicted in FIG. 4A along sectional line 4B, inaccordance with at least one embodiment described herein;

FIG. 4C is a cross-sectional elevation of the illustrative pipelinereinstatement tool depicted in FIG. 4A along sectional line 4C, inaccordance with at least one embodiment described herein;

FIG. 5A is an plan view of an illustrative pipeline reinstatement toolthat includes a flexible shaft having a first end and a second end, acutting head affixed to the first end of the flexible shaft, a pluralityof resilient members disposed about the cutting head, and in which thefirst flexible sleeve includes an external flexible member disposed atleast partially about the first flexible member and the second flexiblesleeve includes an external flexible member disposed at least partiallyabout the second flexible member, in accordance with at least oneembodiment described herein;

FIG. 5B is a cross-sectional elevation of the illustrative pipelinereinstatement tool depicted in FIG. 5A along sectional line 5B, inaccordance with at least one embodiment described herein;

FIG. 5C is a cross-sectional elevation of the illustrative pipelinereinstatement tool depicted in FIG. 5A along sectional line 5C, inaccordance with at least one embodiment described herein;

FIG. 6A is a plan view of an illustrative pipeline reinstatement tool inwhich the cutting head includes one or more apertures formed in thehollow cylindrical shell, and in which the first flexible memberincludes a first portion and a second portion separated by a floatingspacer element, in accordance with at least one embodiment describedherein;

FIG. 6B is a cross-sectional elevation of the illustrative pipelinereinstatement tool depicted in FIG. 6A along sectional line 6B, inaccordance with at least one embodiment described herein;

FIG. 6C is a cross-sectional elevation of the illustrative pipelinereinstatement tool depicted in FIG. 6A along sectional line 6C, inaccordance with at least one embodiment described herein;

FIG. 6D is a cross-sectional elevation of the illustrative pipelinereinstatement tool depicted in FIG. 6A along sectional line 6D, inaccordance with at least one embodiment described herein;

FIG. 7A is a plan view of another illustrative pipeline reinstatementtool in which the cutting head includes a plurality of apertures formedin the hollow cylindrical shell, and in which the first flexible sleeveincludes a first external flexible member and a second external flexiblemember disposed about at least a portion of the flexible member, inaccordance with at least one embodiment described herein;

FIG. 7B is a cross-sectional elevation of the illustrative pipelinereinstatement tool depicted in FIG. 7A along sectional line 7B, inaccordance with at least one embodiment described herein;

FIG. 7C is a cross-sectional elevation of the illustrative pipelinereinstatement tool depicted in FIG. 7A along sectional line 7C, inaccordance with at least one embodiment described herein;

FIG. 7D is a cross-sectional elevation of the illustrative pipelinereinstatement tool depicted in FIG. 7A along sectional line 7D, inaccordance with at least one embodiment described herein;

FIG. 8A is a partial cross-sectional view of an illustrative pipelinereinstatement tool disposed in a lateral pipeline, as the pipelinereinstatement tool approaches a reinstated pipeline that includes apreviously installed liner, in accordance with at least one embodimentdescribed herein;

FIG. 8B is a partial cross-sectional view of the illustrative pipelinereinstatement tool of FIG. 8A after the pipeline reinstatement tool hascut a penetration through the liner to fluidly couple the lateralpipeline to the reinstated pipeline, in accordance with at least oneembodiment described herein;

FIG. 9 is a rearward looking perspective view of the illustrativepipeline reinstatement tool such as depicted in FIG. 2, in accordancewith at least one embodiment described herein;

FIG. 10 is a forward-looking perspective view of the illustrativepipeline reinstatement tool such as depicted in FIG. 2, in accordancewith at least one embodiment described herein;

FIG. 11A is a front elevation view of an illustrative cutting head, inaccordance with at least one embodiment described herein;

FIG. 11B is a side elevation of the illustrative cutting head, inaccordance with at least one embodiment described herein;

FIG. 11C is a rear elevation view of the illustrative cutting head, inaccordance with at least one embodiment described herein;

FIG. 11D is a rear perspective view of the illustrative cutting head, inaccordance with at least one embodiment described herein;

FIG. 11E is a front perspective view of the illustrative cutting head,in accordance with at least one embodiment described herein;

FIG. 11F is a longitudinal cross-sectional side view of the illustrativecutting head, in accordance with at least one embodiment describedherein;

FIG. 12A is a block diagram of an illustrative first flexible sleeve, inaccordance with at least one embodiment described herein;

FIG. 12B is an elevation of an illustrative flexible sleeve, inaccordance with at least one embodiment described herein;

FIG. 12C is a perspective view of an illustrative self-adjustingalignment bushing included in the first flexible sleeve, in accordancewith at least one embodiment described herein;

FIG. 12D is a cross-sectional elevation of an illustrative firstflexible sleeve, such as depicted in FIGS. 12A and 12B, in accordancewith at least one embodiment described herein;

FIG. 13A is a side elevation of an illustrative compressible tensioner,in accordance with at least one embodiment described herein;

FIG. 13B is a cross-sectional elevation of the illustrative compressibletensioner, in accordance with at least one embodiment described herein;

FIG. 14A is a side elevation of an illustrative second flexible sleeve,in accordance with at least one embodiment described herein;

FIG. 14B is a cross-sectional elevation of the illustrative secondflexible sleeve, in accordance with at least one embodiment describedherein;

FIG. 15A is a side elevation of another illustrative cutting head, inaccordance with at least one embodiment described herein;

FIG. 15B is a rear elevation of the illustrative cutting head depictedin FIG. 15A, in accordance with at least one embodiment describedherein;

FIG. 15C is a front elevation of the illustrative cutting head depictedin FIG. 15A and FIG. 15B, in accordance with at least one embodimentdescribed herein;

FIG. 16A is a side elevation view of an illustrative two-piece cuttinghead system that includes a cutting head that is separated from andslideably insertable into a floating spacer member that is slideablydisplaceable along the longitudinal axis of the flexible shaft to exposeat least a portion of the cutting head, in accordance with at least oneembodiment described herein;

FIG. 16B is a side elevation view of the illustrative two-piece cuttinghead as depicted in FIG. 16A in an assembled state, with the cuttinghead inserted into the floating spacer member, in accordance with atleast one embodiment described herein;

FIG. 16C is a front-elevation view of the illustrative assembledtwo-piece cutting head as depicted in FIG. 16B, in accordance with atleast one embodiment described herein;

FIG. 16D is a cross-sectional elevation of the illustrative assembledtwo-piece cutting head as depicted in FIG. 16C along sectional line16D-16D, in accordance with at least one embodiment described herein;

FIG. 16E is a rear-elevation view of the illustrative assembledtwo-piece cutting head as depicted in FIG. 16B, in accordance with atleast one embodiment described herein;

FIG. 16F is a side elevation of an illustrative pipeline reinstatementtool that includes the illustrative two-piece cutting head 1600 depictedin FIGS. 16A-16E, in accordance with at least one embodiment describedherein;

FIG. 17A is a side elevation view of an illustrative dual-blade cuttinghead system that includes a second cutting head disposed coaxially withand at least partially within the first cutting head, such that thedual-blade cutting head formed by the first cutting head and the secondcutting head are slideably insertable into a floating spacer member thatis slideably displaceable along the longitudinal axis of the flexibleshaft to expose at least a portion of the first cutting head and thesecond cutting head, in accordance with at least one embodimentdescribed herein;

FIG. 17B is a side elevation view of the illustrative dual-blade cuttinghead as depicted in FIG. 17A in an assembled state, with the firstcutting head affixed to the second cutting head and inserted into thefloating spacer member, in accordance with at least one embodimentdescribed herein;

FIG. 17C is a front-elevation view of the illustrative assembleddual-blade cutting head as depicted in FIG. 17B, in accordance with atleast one embodiment described herein;

FIG. 17D is a cross-sectional elevation of the illustrative assembleddual-blade cutting head as depicted in FIG. 17C along sectional line17D-17D, in accordance with at least one embodiment described herein;

FIG. 17E is a rear-elevation view of the illustrative assembleddual-blade cutting head 1700 as depicted in FIG. 17B, in accordance withat least one embodiment described herein;

FIG. 17F is a side elevation of an illustrative pipeline reinstatementtool that includes the illustrative dual-blade cutting head 1700depicted in FIGS. 17A-17E, in accordance with at least one embodimentdescribed herein;

FIG. 18A is a side elevation view of an illustrative dual-blade cuttinghead system that includes a second cutting head disposed coaxially withand at least partially within the first cutting head, such that thedual-blade cutting head formed by the first cutting head and the secondcutting head are slideably insertable into a floating spacer member thatis slideably displaceable along the longitudinal axis of the flexibleshaft to expose at least a portion of the first cutting head and thesecond cutting head, in accordance with at least one embodimentdescribed herein;

FIG. 18B is a side elevation view of the illustrative dual-blade cuttinghead as depicted in FIG. 18A in an assembled state, with the firstcutting head affixed to the second cutting head and inserted into thefloating spacer member, in accordance with at least one embodimentdescribed herein;

FIG. 18C is a front-elevation view of the illustrative assembleddual-blade cutting head as depicted in FIG. 18B, in accordance with atleast one embodiment described herein;

FIG. 18D is a cross-sectional elevation of the illustrative assembleddual-blade cutting head as depicted in FIG. 18C along sectional line18D-18D, in accordance with at least one embodiment described herein;

FIG. 18E is a rear-elevation view of the illustrative assembleddual-blade cutting head 1700 as depicted in FIG. 18B, in accordance withat least one embodiment described herein;

FIG. 18F is a side elevation of an illustrative pipeline reinstatementtool that includes the illustrative dual-blade cutting head 1800depicted in FIGS. 18A-18E, in accordance with at least one embodimentdescribed herein;

FIG. 19A is a side elevation view of the illustrative pipelinereinstatement tool in which the compressible tensioner and the secondflexible sleeve have been combined to provide compressible tensionersleeve, in accordance with at least one embodiment described herein;

FIG. 19B is a side elevation view of the illustrative pipelinereinstatement tool depicted in FIG. 19A with an axially applied force(“F”) causing the displacement of the cylindrical floating spacerelement along the flexible shaft, exposing the first cutter head and thesecond cutter head, in accordance with at least one embodiment describedherein;

FIG. 20 is a side elevation view of an illustrative pipelinereinstatement tool that includes a flexible sleeve portion having afirst cylindrical floating spacer element and a second cylindricalfloating spacer element disposed along the flexible shaft and positionedbetween a first compressible tensioner section and a second compressibletensioner section, in accordance with at least one embodiment describedherein;

FIG. 20A is a sectional view of the illustrative pipeline reinstatementtool depicted in FIG. 20 along sectional line 20A-20A, in accordancewith at least one embodiment described herein;

FIG. 20B is a sectional view of the illustrative pipeline reinstatementtool depicted in FIG. 20 along sectional line 20B-20B, in accordancewith at least one embodiment described herein;

FIG. 20C is a sectional view of the illustrative pipeline reinstatementtool depicted in FIG. 20 along sectional line 20C-20C, in accordancewith at least one embodiment described herein;

FIG. 20D is a sectional view of the illustrative pipeline reinstatementtool depicted in FIG. 20 along sectional like 20D-20D, in accordancewith at least one embodiment described herein;

FIG. 21 is a side elevation view of an illustrative pipelinereinstatement tool that includes: a flexible sleeve portion having aflexible member, an external flexible member disposed about at least aportion of an external surface of the flexible member, and twocylindrical floating spacer elements disposed along the flexible shaftand positioned between a first compressible tensioner and a secondcompressible tensioner, in accordance with at least one embodimentdescribed herein; and

FIG. 21A is a sectional view of the illustrative pipeline reinstatementtool 2100 depicted in FIG. 21 along sectional line 21A-21A, inaccordance with at least one embodiment described herein.

Although the following Detailed Description will proceed with referencebeing made to illustrative embodiments, many alternatives, modificationsand variations thereof will be apparent to those skilled in the art.

DETAILED DESCRIPTION

The apparatuses, systems, and methods described herein provide apipeline reinstatement tool capable of passing through lateral pipelinesand penetrating a cured liner disposed within a pipeline. Morespecifically, the apparatuses, systems, and methods detailed hereinprovide a penetration tool capable of reducing to seconds the timerequired to penetrate a liner within a reinstated pipeline whileminimizing or even eliminating damage to the lateral pipeline as thepenetration tool is positioned against the liner in the reinstatedpipeline. The apparatuses disclosed herein include a penetration toolhaving a cutting head that, when passed through a lateral pipeline andpositioned in contact with the cured liner in a reinstated pipeline,quickly and efficiently penetrates the cured liner.

The apparatuses, systems, and methods described herein provide apenetration tool that includes a cutting head, a first flexible sleeve,a second flexible sleeve, and a compressible tensioner disposed on aflexible shaft. The cutting head is disposed on a first end of theflexible shaft, the first flexible sleeve is disposed proximate thecutting head, and the compressible tensioner is positioned along theflexible shaft, between the first flexible sleeve and the secondflexible sleeve. The flexible shaft extends through the second flexiblesleeve, the compressible tensioner, and the first flexible sleeve. Theflexible shaft also extends through a mounting feature coupled to thecutting head and a plurality of fasteners disposed in the mountingfeature are used to detachably attach the cutting head to a fixedposition proximate the first end of the flexible shaft. The firstflexible sleeve proximate the cutting head extends a greater distancealong the flexible shaft than the second flexible sleeve proximate acoupler attached proximate the second end of the flexible shaft.

One or more spacers may be positioned along the flexible shaft. The oneor more spacers assist in keeping the cutting head centered in thelateral, beneficially centering the hole formed by the cutter bit in thecured liner within the reinstated pipe. By centering the cutting headwithin the lateral pipe, the risk of the cutting head damaging thelateral pipe is reduced or even eliminated. The one or more spacers maybe positioned along the flexible shaft, along the first flexible sleeve,and/or along the second flexible sleeve. The one or more spacers mayinclude one or more 2-dimensional (e.g., disk-shaped member(s),snowflake-shaped member(s), or similar) or 3-dimensional (e.g.,spherical members, hemispherical members, or similar) or combinationsthereof.

The cutting head includes a hollow cylindrical member having a pluralityof teeth extending longitudinally outward from a first end of the hollowcylindrical member. The number, spacing, and composition of the teethmay be adjusted based upon the composition of the lateral pipe, thecomposition of the reinstated pipeline, and/or the composition of theliner inside the reinstated pipeline. A slideably displaceable sheathmay be disposed proximate the external surface of the hollow cylindricalmember. The slideably displaceable sheath may have a thickness greaterthan the lateral distance the teeth extend from the external surface ofthe cutting head such that the slideably displaceable sheathadvantageously reduces or even prevents the teeth from contacting thesidewall of the lateral pipe as the cutting head is rotated andpenetrates the liner within the reinstated pipeline. One or moreelastomeric rings may be disposed about the external surface of thecutting head. Similar to the slideably displaceable sheath, the one ormore elastomeric rings may have a thickness that exceeds the radialprojection of the teeth from the external surface of the cutting head.Thus, like the slideably displaceable sheath, the one or moreelastomeric rings advantageously reduce or even prevent the teeth fromcontacting the sidewall of the lateral pipe as the cutting head isrotated and penetrates the liner within the reinstated pipeline.

The first flexible sleeve may include a tightly coiled helical member,for example a tightly coiled metal spring. A self-adjusting alignmentbushing may be disposed on either or both ends of the first flexiblesleeve. The self-adjusting alignment bushing may threadedly engage theexternal surface of the first flexible sleeve. The self-adjustingalignment bushing beneficially adjusts the rigidity of the penetrationtool—as the first flexible sleeve is advanced into the self-adjustingalignment bushing, the rigidity or stiffness of the penetration tool isincreased. As the first flexible sleeve is withdrawn from theself-adjusting alignment bushing, the rigidity or stiffness of thepenetration tool is decreased. Thus, to insert the penetration tool thefirst flexible sleeve may be withdrawn from the self-adjusting alignmentbushing to permit the penetration tool to pass through fittings in thelateral pipe. Upon contacting the liner in the reinstated pipeline androtating the cutting head, the first flexible sleeve may advance intothe self-adjusting alignment bushing, beneficially increasing thestiffness of the penetration tool and advantageously increasing theability of the system operator to apply pressure to the cutting head,thereby speeding the penetration of the liner in the reinstatedpipeline. The compressible tensioner permits an operator to maintain aconstant pressure along the flexible shaft to the cutting head as thebit “bites” into the liner within the reinstated pipeline and as thecutting head penetrates the liner.

A pipeline reinstatement tool is provided. The tool may include: aflexible shaft having a first length, a first end, and a second end; acutting head coupled to the first end of the flexible shaft, the cuttinghead including: a hollow cylindrical member having a first end, a secondend, an internal surface and an external surface; and cutting teethdisposed on a first end of the hollow cylindrical member and extendinglongitudinally from the first end of the hollow cylindrical member; afirst flexible sleeve disposed around the flexible shaft proximate thecutting head, the first flexible sleeve having a first sleeve lengththat extends a first distance along the flexible shaft; a secondflexible sleeve disposed around the flexible shaft, the second flexiblesleeve having a second sleeve length that extends a second distancealong the flexible shaft; wherein the second sleeve length is less thanthe first length of the first sleeve length; and a compressibletensioner disposed about the flexible shaft between the first flexibleelement and the second flexible element.

A pipeline reinstatement tool is provided. The tool may include: aflexible shaft having a first length, a first end, and a second end; acutting head coupled to the first end of the flexible shaft, the cuttinghead including: a hollow cylindrical member having a first end, a secondend, an internal surface and an external surface; and cutting teethdisposed on a first end of the hollow cylindrical member and extendinglongitudinally from the first end of the hollow cylindrical member; afirst flexible sleeve disposed around the flexible shaft proximate thecutting head, the first flexible sleeve having a first sleeve lengththat extends a first distance along the flexible shaft, the firstflexible sleeve including: a first flexible member having an externalsurface, a first end, a second end, and an inside diameter through whichthe flexible shaft freely passes; a first self-adjusting alignmentbushing coupled to the first end of the first flexible member; a secondself-adjusting alignment bushing coupled to the second end of the firstflexible shaft; and at least one floating spacer element disposedproximate the first flexible member; a second flexible sleeve disposedaround the flexible shaft, the second flexible sleeve having a secondsleeve length that extends a second distance along the flexible shaft,wherein the second sleeve length is less than the first sleeve length,the second flexible sleeve including: a second flexible member having afirst end, a second end, and an inside diameter through which theflexible shaft freely passes; and a first self-adjusting alignmentbushing coupled to the first end of the second flexible shaft; and acompressible tensioner disposed about the flexible shaft between thefirst flexible element and the second flexible element, the compressibletensioner including: a compressible element having a first end and asecond end; a first annular connector coupled to the first end of thecompressible element; and a second annular connector coupled to thesecond end of the compressible element.

As used herein the term “axial” refers to the longitudinal axis of theflexible shaft of the pipeline reinstatement tool. As used herein, theterm “radial” refers to a radius, radial member, or radial distancemeasured with respect to the longitudinal axis of the flexible shaft ofthe pipeline reinstatement tool.

FIG. 1 is a block diagram depicting an illustrative pipelinereinstatement tool 100 that includes a flexible shaft 110, a cuttinghead 120 affixed to a first end of the flexible shaft 110, a firstflexible sleeve 140 having a first axial length (L₁) 141, a compressibletensioner 160, a second flexible sleeve 180 having a second axial length(L₂) 181, and a coupling assembly 190 that couples a second end of theflexible shaft 110 to a rotatable external drive shaft 114, inaccordance with at least one embodiment described herein. In operation,the pipeline reinstatement tool 100 is inserted through a lateralpipeline that is connected to a lined reinstated pipeline. When thepipeline reinstatement tool 100 contacts the liner in the reinstatedpipeline, the cutting head 120 rotates at high speed to cut through theliner and fluidly couple the lateral pipeline with the lined, reinstatedpipeline. The first flexible sleeve 140 and the second flexible sleeve180 permit the pipeline reinstatement tool 100 to pass through fittingsin the lateral pipeline. The compressible tensioner 160 permits theapplication of an axial force on the cutting head 120 to cause thecutting head to initially bite into the liner inside the reinstatedpipeline and eventually to cut through the liner to form a fluidconnection between the lateral pipeline and the lined reinstatedpipeline. The pipeline reinstatement tool 100 as described hereinbeneficially and advantageously performs such penetrations in a fractionof the time required using current reinstatement tools.

The flexible shaft 110 permits the pipeline reinstatement tool 100 topass through and around fittings in the lateral pipeline. The first endof the flexible shaft 110 couples to the cutting head 120 and theopposite, second, end of the flexible shaft 110 couples to a couplingassembly 190. The cutting head 120 may be affixed to or detachablyattached to the flexible shaft 110, for example using a plurality ofthreaded fasteners. The coupling assembly 190 may be affixed ordetachably attached to the flexible shaft 110, for example using aplurality of threaded fasteners. In embodiments, the flexible shaft 110may include a plurality off operably coupled individual segments.

The flexible shaft 110 can have any axial length measured along thelongitudinal axis 112 of the flexible shaft 110. In embodiments, theflexible shaft 110 may have a length of less than: about 4 inches (in);about 6 in; about 8 in; about 12 in; about 18 in; about 24 in; or about36 in. The flexible shaft 110 can have any diameter measured transverseto the longitudinal axis 112 of the flexible shaft 110. In embodiments,the flexible shaft 110 may have a diameter of less than: about 1/16inch; about ⅛ in; about ¼ in; about ⅜ in; about ½ in; about ⅝ in; orabout ¾ in. The flexible shaft 110 may be fabricated using any metallic,non-metallic, or composite material. In some embodiments, the flexibleshaft 110 may include a metallic, tightly wound coiled member.

The first axial length 141 of the first flexible sleeve 140 is greaterthan the second axial length 181 of the second flexible sleeve 180. Inembodiments, the ratio of the second axial length 181 to the first axiallength 141 is less than: about 0.1; about 0.2; about 0.3; about 0.4;about 0.5; about 0.7; about 0.8; or about 0.9. In embodiments, the firstaxial length 141 may be less than: about 10%; about 20%; about 33%;about 40%; about 50%; about 60%; or about 70% of the length 111 of theflexible shaft 110. In embodiments, the second axial length 181 may beless than: about 5%; about 10%; about 20%; about 30%; or about 40% ofthe length 111 of the flexible shaft 110.

The cutting head 120 includes a plurality of teeth 122A-122 n(collectively, “teeth 122”) that extend longitudinally from a first endof the cutting head 120 and are generally parallel to the longitudinalaxis 112 of the flexible shaft 110. One or more recesses or grooves 124may be formed in the external surface of the cutting head 120. Inembodiments, the one or more grooves 124 may include one or more helicalor spiral grooves formed in the external surface of the cutting head120. In embodiments, the second end of the cutting head 120 may beradiused or chamfered 126 to ease withdrawal of the pipelinereinstatement tool 100 from the reinstated pipeline after the pipelinereinstatement tool 100 penetrates the liner within the reinstatedpipeline. The cutting head 120 can have any outside diameter. Forexample, the cutting head 120 may have an outside diameter of: less than1 inch (in); less than 1½ in; less than 2 in; less than 2½ in; less than3 in; less than 4 in; or less than 6 in.

FIG. 2A is an plan view of an illustrative pipeline reinstatement tool200 that includes a flexible shaft 110 having a first end and a secondend, a cutting head 120 affixed to the first end of the flexible shaft110, a first flexible sleeve 140, a second flexible sleeve 180, acompressible tensioner 160 disposed between the first flexible sleeve140 and the second flexible sleeve 180, and a coupling assembly 190disposed proximate the second end of the flexible shaft 110, inaccordance with at least one embodiment described herein. FIGS. 2B, 2C,2D, 2E, 2F, 2G, 2H, 2I, and 2J provide cross-sectional elevations of thepipeline reinstatement tool 200 at the respective points indicated inFIG. 2A. In operation, the pipeline reinstatement tool 200 is passedthrough a lateral pipeline until the cutting head 120 contacts a curedliner previously installed in a reinstated pipeline. The flexible shaft110 is rotated, causing the cutting head 120 to rotate at a similarspeed. The first flexible sleeve 140 and the second flexible sleeve 180provide the ability to maneuver the pipeline reinstatement tool 100through fittings and/or valves disposed in the lateral pipeline.

As depicted in FIG. 2A, the first flexible sleeve 140 includes aflexible member 242 through which the flexible shaft 110 passes. Aplurality of fixed spacer elements 244A-244 n (collectively, “fixedspacer elements 244”) are affixed to the external surface of theflexible member 242. A plurality of floating spacer elements 246A-246 n(collectively, “floating spacer elements 246”) are disposed proximatethe external surface of the flexible member 242 and are able to rotateabout the flexible member 242 and slide along at least a portion of thelength of the flexible member 242. A plurality of self-adjustingalignment bushings 250A, 250B (collectively, “self-adjusting alignmentbushings 250”) couple to the first end and the second end of the firstflexible member 242, respectively. In at least some embodiments, theself-adjusting alignment bushings 250 are displaceable with respect tothe first flexible sleeve 140. In some implementations, theself-adjusting alignment bushings may threadedly engage the externalsurface of the first flexible member 242.

The second flexible sleeve 180 includes a second flexible member 282through which the flexible shaft 110 passes. The second flexible member282 includes a first end and second end. In embodiments the second endof the second flexible sleeve 180 proximate the coupling assembly 190may be flared outward and may be disposed proximate an attachmentfixture 190 that is affixed to the flexible shaft 110. A self-adjustingalignment bushing 284 couples to the first end second flexible sleeve282. In at least some embodiments, the self-adjusting alignment bushing284 is displaceable with respect to the second flexible member 282. Insome implementations, the self-adjusting alignment bushing 284 maythreadedly engage the external surface of the second flexible member282. In embodiments, the axial length of the second flexible sleeve 180(i.e., the length the second flexible sleeve 180 extends along theflexible shaft 110) is less than the axial length of the first flexiblesleeve 140 (i.e., the length the first flexible sleeve 140 extends alongthe flexible shaft 110). In other embodiments, the axial length of thesecond flexible sleeve 180 may be greater than the axial length of thefirst flexible sleeve 140.

A plurality of positioning elements 254A-254 n (collectively,“positioning elements 254”) that extend radially outward from theflexible shaft 110 are disposed at various locations along the axiallength of the flexible shaft 110. The positioning elements 254 assist inmaintaining the pipeline reinstatement tool 200 centered in the lateralpipe as the pipeline reinstatement tool 200 passes through the lateralpipe. In addition, the positioning elements 254 also assist inpreventing the cutting head 120 from contacting the sidewall of thelateral pipe as the pipeline reinstatement tool 200 rotates to cutthrough the liner disposed in the reinstated pipeline. The each of thepositioning elements 254 may include one or more individual planarpositioning elements 254 that are stacked along the longitudinal axis112 of the flexible shaft 110.

The flexible shaft 110 may include any member capable of transmittingrotational motion provided by an external device (e.g., a rotating toolsuch as a mini-Miller or maxi-Miller) to the cutting head 120 via thecoupling assembly 190. The flexible shaft 110 may be fabricated usingany metallic, non-metallic, or composite material capable oftransmitting the torque applied by the external device via the externalshaft 114 and coupling assembly 190. For example, the flexible shaft 110may be fabricated, in whole or in part, using a high tensile strengthtightly coiled metal shaft. In another embodiment, the flexible shaft110 may be fabricated, in whole or in part, using a carbon fiber shaft.In yet another example, the flexible shaft 110 may be fabricated, inwhole or in part, using a composite shaft having a carbon fiber/metalconstruction.

Referring to FIGS. 2A and 2B, the cutting head 120 includes a hollowcylindrical member 230 having an inner surface 232 and an outer surface234. The hollow cylindrical member 230 coaxially aligns with thelongitudinal axis 112 of the flexible shaft 110. A plurality of teeth122A-122 n (collectively, “teeth 122”) parallel to the longitudinal axis112 of the flexible shaft 110 extend from the first end of the cuttinghead 120. In embodiments, the teeth 122 may extend radially outward fromthe external surface 234 of the hollow cylindrical member 230.

The cutting head 120 includes an attachment member 236 that is disposedtransverse to the longitudinal axis 112 of the flexible shaft 110. Theattachment member 236 is affixed to the hollow cylindrical member 230.In embodiments, the attachment member 236 may be affixed to the internalsurface 232 of the hollow cylindrical member 230. The attachment member236 may be affixed proximate the second end of the hollow cylindricalmember 230 or may be affixed at an intermediate location between thefirst end and the second end of the hollow cylindrical member 230. Inembodiments, the first end of the flexible shaft 110 may pass through anaperture 238 formed in the attachment member 236. In embodiments, thefirst end of the flexible shaft 110 may extend through the attachmentmember 236 and may project into the interior of the hollow cylindricalmember 230.

In embodiments, the cutting head 120 detachably attaches to the firstend of the flexible shaft 110, for example using one or more threadedfasteners or similar attachment devices. In other embodiments, thecutting head 120 is affixed to the first end of the flexible shaft 110,for example by compression fitting, stamping, or welding. Inembodiments, the attachment member 236 may include an aperture 238through which the first end of the flexible shaft 110 passes, allowingthe cutting head 120 to be axially positioned proximate the first end ofthe flexible shaft 110. In embodiments, the aperture 238 may be disposedat a central location within the attachment member 236.

A number of grooves 124 may be formed circumferentially about all or aportion of the external surface of the hollow cylindrical member 230. Inembodiments, one or more helical grooves 124 may be formed about all ora portion of the external surface of the hollow cylindrical member 230.Such groves 124 may beneficially permit the escape of detritus and wastematerial from the location where the cutting head 120 contacts the linerinside the reinstated pipeline. The second end of the hollow cylindricalmember 230 may be chamfered or rounded 126 to permit retraction orwithdrawal of the cutting head 120 from the reinstated pipelinepenetrating the liner.

The cutting head 120 may be formed using any suitably rigid, resilientmaterial. For example, the cutting head 120 may be fabricated in wholeor in part using tungsten carbide or similar materials. In otherembodiments, the hollow cylindrical member 230 may be formed using afirst material and the teeth 122 formed using a second material. Thecutting head 120 may have any diameter and height or axial length. Inembodiments, the cutting head 120 may have a diameter of about: 1 inchor less; 2 inches or less; 3 inches or less; 4 inches or less; or about6 inches or less. In embodiments, the cutting head 120 may have a heightor axial length of about: 1 inch or less; 2 inches or less; 3 inches orless; 4 inches or less; or about 6 inches or less. The cutting head 120may have any number of teeth 122 disposed on the first end of the hollowcylindrical member. For example, the cutting head 120 may have 4 or moreteeth; 8 or more teeth; 12 or more teeth; 16 or more teeth; or 20 ormore teeth. In embodiments, the teeth 122 may have a triangular cuttingsurface. In embodiments, each of the plurality of teeth 122 may havesimilar or identical cutting surface profiles. In other embodiments, atleast some of the plurality of teeth 122 may have different cuttingsurface profiles.

In embodiments, one or more positioning elements 254A may be disposedbetween the cutting head 120 and the first flexible sleeve 140. Thepositioning elements 254A beneficially minimize the likelihood of thecutting head 120 contacting the inner surface of the lateral pipe as thecutting head 120 is rotated. The one or more positioning elements 254may include any number of planar member having an aperture disposedtherethrough to accommodate the passage of the flexible shaft 110. Inembodiments, the aperture formed in the one or more positioning elements254A may include a central aperture such that the one or morepositioning elements 254A are symmetric about the flexible shaft 110. Inembodiments, the one or more positioning elements 254A may be freefloating about the flexible shaft 110. The one or more positioningelements 254A may be fabricated using any material that does not mar ordamage the lateral pipe through which the pipeline reinstatement tool200 is passed. For example, the one or more positioning elements 254Amay be fabricated using one or more of: carbon fiber; propylene,polypropylene, ethylene propylene diene monomer (EPDM); polyvinylchloride (PVC); chlorinated PVC (CPVC); polybutylene; or similar.

Each of the one or more positioning elements 254A may have the same ordifferent diameters and/or thicknesses. In embodiments, at least some ofthe positioning elements 254A may have an outside diameter that isapproximately the same as the outside diameter of the hollow cylindricalmember 230 forming the cutting head 120. In embodiments, at least someof the positioning elements 254A may have an outside diameter that isslightly larger than the outside diameter of the hollow cylindricalmember 230 by about: 1/16 inch; ⅛ inch; ¼ inch; or ½ inch. Inembodiments, at least some of the positioning elements 254A may have anoutside diameter that is slightly smaller than the outside diameter ofthe hollow cylindrical member 230 by about by about: 1/16 inch; ⅛ inch;¼ inch; or ½ inch. Each of the positioning elements 254A may have athickness of about: 1/32 inch or less; 1/16 inch or less; ⅛ inch orless; ¼ inch or less; or ½ inch or less.

Referring next to FIGS. 2A, 2C, 2D, 2E, 2F, 2G, and cross sections A andB, the first flexible sleeve 140 includes a first flexible member 242,having a self-adjusting alignment bushings 250 coupled to the first andsecond ends of the first flexible member 242. In embodiments, the firstflexible member 242 may include a tightly coiled member such as atightly coiled spring or similar. As depicted in cross-sections A and B,the self-adjusting alignment bushings 250A, 250B may include internal(i.e., female) threads 252A, 252B (respectively) such that THE tightlycoiled first flexible member 242 may threadedly engage the alignmentbushings 250.

Beneficially, as the first flexible member 242 advances into theself-adjusting alignment bushings 250, the stiffness of the firstflexible sleeve 140 increases. As the first flexible member 242withdraws from the self-adjusting alignment bushings 250, the stiffnessof the first flexible sleeve decreases. Thus, the first flexible member242 may be at least partially withdrawn from the self-adjustingalignment bushings 250 to increase the flexibility of the first flexiblesleeve and ease the insertion of the pipeline reinstatement tool 200 ina lateral pipe. As the cutting head 120 contacts the liner in thereinstated pipeline, the self-adjusting alignment bushings 250 threadonto the first flexible member 242, beneficially increasing thestiffness of the pipeline reinstatement tool 200 and permitting the tooloperator to increase the force applied to the pipeline reinstatementtool 200, advantageously reducing the time required to penetrate theliner within the reinstated pipeline.

The first flexible member 242 may have any length and/or diameter. Inembodiments, the first flexible member 242 may have a length of about10%, about 20%, about 30%, about 40%, about 50%, or about 70% of thelength of the flexible shaft 110. For example, in one embodiment, theflexible shaft 110 may have a length of 15 inches and the first flexiblemember 242 may have a length of about 7½ inches (about 50% of the lengthof the flexible shaft 110). The first flexible member 242 may befabricated using any suitable metallic, non-metallic, or compositematerial. For example, the first flexible member 242 may be fabricated,in whole or in part, as a tightly wound metallic coil spring. In anotherexample, the first flexible member 242 may include a carbon fiber springor a polymeric spring. In another example, the first flexible member 242may include a continuous tube fabricated using one or more flexiblematerials and/or fabrics. The first flexible member 242 may have auniform or non-uniform construction. For example, the first flexiblemember 242 may have a tightly coiled metal first end and a tightlycoiled metal second end connected by a flexible, smooth, metallic ornon-metallic intermediate section.

The self-adjusting alignment bushings 250 may be fabricated using anymaterial or combination of materials capable of engaging the externalsurface of the first flexible member 242. In some embodiments, theself-adjusting alignment bushings 250 are axially displaceable along theexternal surface of the first flexible member 242. In at least someimplementations, the self-adjusting alignment bushings 250 maythreadedly engage the external surface of the first flexible member 242.

The diameter of the self-adjusting alignment bushings 250 may be thesame or different. The diameter of the self-adjusting alignment bushings250 is less than the diameter of the hollow cylindrical member 230. Inembodiments, the self-adjusting alignment bushings 250 may befabricated, in whole or in part, using a metallic material demonstratingadequate corrosion resistance in the expected operating environment.Example metallic materials include but are not limited to: brass,bronze, stainless steel, and similar. In other embodiments, theself-adjusting alignment bushings 250 may be fabricated, in whole or inpart, using a non-metallic material. Example non-metallic materialsinclude but are not limited to: polypropylene, EPDM, polyoxymethylene(Delrin®), PVC, CPVC, fiber reinforced plastic (FRP), carbon fiber, orcombinations thereof. In embodiments, the self-adjusting alignmentbushings 250 may include a metallic member that is coated with one ormore non-metallic materials.

One or more fixed spacer elements 244A-244 n are disposed at equal orunequal intervals along the axial length of the first flexible member242. In embodiments, the one or more fixed spacer elements 244 may beaffixed to the external surface of the first flexible member 242 suchthat the one or more fixed spacer elements 244 are not axiallydisplaceable along all or a portion of the axial length of the firstflexible member 242. In embodiments, the outside diameter of some or allof the fixed spacer elements 244 may be the same as or similar to theoutside diameter of the hollow cylindrical member 230. In someembodiments, the one or more fixed spacer elements 244 may be formedintegral with the first flexible member 242. In other embodiments, theone or more fixed spacer elements 244 may be separately fabricated andaffixed to the external surface of the first flexible member 242, suchas via one or more fasteners, one or more adhesives, or via press orcompression fitting.

Although depicted as discs, the one or more fixed spacer elements 244may have any physical shape or geometry. For example, some or all of theone or more fixed spacer elements may be frustoconical, hemispherical,ovoid, spherical, or combinations thereof. The one or more fixed spacerelements 244 may be fabricated using any metallic or non-metallicmaterial that will not damage the interior surface of the lateral pipeas the pipeline reinstatement tool 100 is passed through the lateralpipe. The one or more fixed spacer elements 244 minimize or eliminatethe possibility of the first flexible member 242 and the flexible shaft110 from contacting the interior of the lateral pipeline as the cuttinghead 120 rotates. Each of the one or more fixed spacer elements 244 maybe fabricated from the same or different materials. In embodiments, theone or more fixed spacer elements 244 may be fabricated using one ormore non-metallic materials such as: polypropylene, EPDM,polyoxymethylene (Delrin®), PVC, CPVC, fiber reinforced plastic (FRP),carbon fiber, and combinations thereof. In embodiments, the one or morefixed spacer elements 244 may be fabricated using one or more metallicmaterials such as: brass, nickel, stainless steel, and similar.

Each of the one or more fixed spacer elements 244 includes an annularspace through which the first flexible member 242 and the flexible shaft110 passes. The inside diameter of the annular space through each of theone or more fixed spacer elements 244 is therefore based on the outsideor external diameter of the first flexible member 242. Each of the oneor more fixed spacer elements 244 may have the same or different outsidediameters. The diameter of each of the one or more fixed spacer elements244 may be based on the outside diameter of the hollow cylindricalmember 230 forming the cutting head 120. For example, the diameter ofeach of the one or more fixed spacer elements 244 may be: about 70% orless; about 80% or less; about 90% or less; about 100% or less; or about110% or less than the outside diameter of the hollow cylindrical member230.

One or more floating spacer elements 246A-246 n are disposed at equal orunequal intervals along the axial length of the first flexible member242. In embodiments, the one or more floating spacer elements 246 may bedisposed about the first flexible member 242 such that the floatingspacer elements 246 are able to rotate about the external surface of thefirst flexible member 242, slide axially along at least a portion of theexternal surface of the first flexible member 242, or both rotate andslide about the external surface of the first flexible member 242. Inembodiments, the outside diameter of some or all of the floating spacerelements 246 may be smaller than the outside diameter of the hollowcylindrical member 230.

Although depicted as rings, the one or more floating spacer elements 246may have any physical shape or geometry. For example, some or all of theone or more floating spacer elements 246 may be frustoconical,hemispherical, ovoid, spherical, or combinations thereof. The one ormore floating spacer elements 246 may be fabricated using any metallicor non-metallic material that will not mar, erode, or otherwise damagethe interior surface of the lateral pipe as the pipeline reinstatementtool 100 is passed through the lateral pipe. The one or more floatingspacer elements 246 minimize or eliminate the possibility of the firstflexible member 242 and/or the flexible shaft 110 from contacting theinterior of the lateral pipeline as the cutting head 120 rotates. Eachof the one or more floating spacer elements 246 may be fabricated fromthe same or different materials. In embodiments, the one or morefloating spacer elements 246 may be fabricated using one or morenon-metallic materials such as: polypropylene, EPDM, polyoxymethylene(Delrin®), PVC, CPVC, fiber reinforced plastic (FRP), carbon fiber, orsimilar. In embodiments, the one or more floating spacer elements 246may be fabricated using one or more metallic materials such as: brass,nickel, stainless steel, and similar.

Each of the one or more floating spacer elements 246 includes an annularspace through which the first flexible member 242 and the flexible shaft110 passes. The inside diameter of the annular space through each of theone or more floating spacer elements 246 is therefore based on theoutside or external diameter of the first flexible member 242. Theinside diameter of the annular space through each of the one or morefloating spacer elements 246 is slightly larger than the externaldiameter of the first flexible member 242. For example, each of the oneor more floating spacer elements 246 may have an inside diameter ofabout 105% or less, about 110% or less; or about 125% or less of theoutside diameter of the first flexible member 242. The diameter of eachof the one or more floating spacer elements 246 may be based on theoutside diameter of the hollow cylindrical member 230 forming thecutting head 120. For example, the diameter of each of the one or morefloating spacer elements 244 may be: about 10% or less; about 20% orless; about 30% or less; about 40% or less; or about 50% or less thanthe outside diameter of the hollow cylindrical member 230.

In embodiments, one or more positioning elements 254B may be disposedbetween the first flexible sleeve 140 and the compressible tensioner160. The positioning elements 254B beneficially minimize the likelihoodof the pipeline reinstatement tool 100 contacting the inner surface ofthe lateral pipe as the cutting head 120 is rotated. The one or morepositioning elements 254B may include any number of planar member havingan aperture disposed therethrough to accommodate the passage of theflexible shaft 110. In embodiments, the aperture formed in the one ormore positioning elements 254B may include a central aperture such thatthe one or more positioning elements 254B are symmetric about theflexible shaft 110. The aperture formed in the one or more positioningelements 254B may have a diameter sufficient to permit the free passageof the flexible shaft 110.

In embodiments, the one or more positioning elements 254B may be freefloating about the flexible shaft 110. The one or more positioningelements 254B may be fabricated using any material that does not mar ordamage the lateral pipe through which the pipeline reinstatement tool100 is passed. For example, the one or more positioning elements 254Bmay be fabricated using one or more of: carbon fiber; propylene,polypropylene, ethylene propylene diene monomer (EPDM); polyvinylchloride (PVC); chlorinated PVC (CPVC); polybutylene; fiber reinforcedplastic (FRP); carbon fiber: or combinations thereof.

Each of the one or more positioning elements 254B may have the same ordifferent diameters and/or thicknesses. In embodiments, at least some ofthe positioning elements 254B may have an outside diameter that isapproximately the same as the outside diameter of the hollow cylindricalmember 230 forming the cutting head 120. In embodiments, at least someof the positioning elements 254B may have an outside diameter that isabout 105% or less; about 110% or less; or about 125% or less than theoutside diameter of the hollow cylindrical member 230. In embodiments,at least some of the positioning elements 254B may have an outsidediameter that is about 95% or less; about 90% or less; about 75% orless; or about 50% or less than the outside diameter of the hollowcylindrical member 230. Each of the positioning elements 254B may have athickness of about: 1/32 inch or less; 1/16 inch or less; ⅛ inch orless; ¼ inch or less; or ½ inch or less.

Referring next to FIGS. 2A, 2H, and 2I, in embodiments, the compressibletensioner 160 includes a helical coil spring 262 with annular connectors270A, 270B (collectively, “annular connectors 270”) coupled to the firstend and the second end of the helical coil spring 262. The flexibleshaft 110 passes through the central aperture formed in the compressibletensioner 160. The central aperture formed through the compressibletensioner 160 is slightly larger in inside diameter than the outsidediameter of the flexible shaft 110. For example, the central aperturethrough the coil spring 262 and annular connectors 270 may have aninside diameter that is at least 100% but less than about 105%; 110%;115%; 120%; 125%; or 250% of the outside diameter of the flexible shaft110.

The helical coil spring 262 may include a metallic spring element havingany number of turns. The helical coil spring 262 may have a springconstant of about: 2 pounds/inch (lb/in) or less; 3 lb/in or less; 5lb/in or less; 7 lb/in or less; 9 lb/in or less; 11 lb/in or less; 15lb/in or less; 20 lb/in or less; or 25 lb/in or less. The helical coilspring 262 may have about 5 useable turns or less; 10 useable turns orless; or 20 useable turns or less. The helical coil spring 262 may havean uncompressed length of about: 10% or less; 20% or less; 30% or less;40% or less; 50% or less; or 60% or less of the length of the flexibleshaft 110. The helical coil spring 262 may be fabricated using anymetallic or non-metallic material. Examples of such materials include,but are not limited to: stainless steel, nickel, brass, carbon fiber, orcombinations thereof. Although the helical coil spring 262 isillustrated, any similar resilient, compressible member (e.g., othertypes of springs) may be used in the compressible tensioner 160.

The annular connectors 270 may be affixed or detachably attached to thehelical coil spring 262. In embodiments, the annular connectors 270 mayhave an outside diameter that is slightly larger than the helical coilspring 262 to accommodate the at least partial insertion of the helicalcoil spring 262 into the annular connector 270A, 270B.

The annular connectors 270 may be fabricated using any material orcombination of materials. The diameter of the annular connectors 270Aand 270B may be the same or different. The diameter of the annularconnectors 270 is less than the diameter of the hollow cylindricalmember 230. In embodiments, the annular connectors 270 may befabricated, in whole or in part, using a metallic material thatdemonstrates adequate corrosion resistance in the expected operatingenvironment. Example metallic materials include but are not limited tobrass, bronze, stainless steel, and similar. In other embodiments, theannular connectors 270 may be fabricated, in whole or in part, using anon-metallic material. Example non-metallic materials include but arenot limited to: polypropylene, EPDM, polyoxymethylene (Delrin®), PVC,CPVC, fiber reinforced plastic (FRP), carbon fiber, or combinationsthereof. In embodiments, the annular connectors 270 may include ametallic core member that is covered, encapsulated, and/or coated withone or more non-metallic materials.

In embodiments, one or more positioning elements 254C may be disposedbetween the compressible tensioner 160 and the second flexible sleeve180. The positioning elements 254C beneficially minimize the likelihoodof the pipeline reinstatement tool 100 contacting the inner surface ofthe lateral pipe as the cutting head 120 is rotated. The one or morepositioning elements 254C may include any number of planar member havingan aperture disposed therethrough to accommodate the passage of theflexible shaft 110. In embodiments, the aperture formed in the one ormore positioning elements 254C may include a central aperture such thatthe one or more positioning elements 254C are symmetric about theflexible shaft 110. The aperture formed in the one or more positioningelements 254C may have a diameter sufficient to permit the free passageof the flexible shaft 110.

In embodiments, the one or more positioning elements 254C may be freefloating about the flexible shaft 110. The one or more positioningelements 254C may be fabricated using any material that does not mar ordamage the lateral pipe through which the pipeline reinstatement tool100 is passed. For example, the one or more positioning elements 254Cmay be fabricated using one or more of: carbon fiber; propylene,polypropylene, ethylene propylene diene monomer (EPDM); polyvinylchloride (PVC); chlorinated PVC (CPVC); polybutylene; fiber reinforcedplastic (FRP); carbon fiber: or combinations thereof.

Each of the one or more positioning elements 254C may have the same ordifferent diameters and/or thicknesses. In embodiments, at least some ofthe positioning elements 254C may have an outside diameter that isapproximately the same as the outside diameter of the hollow cylindricalmember 230 forming the cutting head 120. In embodiments, at least someof the positioning elements 254C may have an outside diameter that is atleast 100%, but less than: about: 105%; about 110%; or about 125% of theoutside diameter of the hollow cylindrical member 230. In embodiments,at least some of the positioning elements 254C may have an outsidediameter that is about 95% or less; about 90% or less; about 75% orless; or about 50% or less than the outside diameter of the hollowcylindrical member 230. Each of the positioning elements 254C may have athickness of about: 1/32 inch or less; 1/16 inch or less; ⅛ inch orless; ¼ inch or less; or ½ inch or less.

Referring next to FIGS. 2A, 2J, and cross section C, the second flexiblesleeve 180 includes a second flexible member 282, having a bushing 284coupled to the first end of the second flexible member 282. Inembodiments, the second flexible member 282 may include a tightly coiledmember such as a tightly coiled spring or similar. As depicted in FIG.2A, in embodiments, the second end of the second flexible member 282 maybe flared outward and at least partially cover the coupling assembly190. In some embodiments, the bushing 284 is axially displaceable alongthe external surface of the second flexible member 282. In at least someimplementations, the bushing 284 may threadedly engage the externalsurface of the second flexible member 282. As depicted in cross-sectionC, in embodiments, the bushing 284 may include internal (i.e., female)threads 186 such that a tightly coiled second flexible member 282 maythreadedly engage the bushing 282.

The second flexible member 282 has an axial length that is shorter orless than the axial length of the first flexible member 242. Inembodiments, the second flexible member 282 may have a length that isabout 10%, about 20%, about 30%, about 40%, about 50%, or about 70% ofthe length of the first flexible member 242. The second flexible member282 may be fabricated using any suitable metallic, non-metallic, orcomposite material. For example, the second flexible member 282 may befabricated, in whole or in part, as a tightly wound metallic coilspring. In another example, the second flexible member 282 may include acarbon fiber spring or a polymeric spring. In another example, thesecond flexible member 282 may include a continuous tube fabricatedusing one or more flexible materials and/or fabrics. The second flexiblemember 282 may have a uniform or non-uniform construction. For example,the second flexible member 282 may have a tightly coiled metal first endand a tightly coiled metal second end connected by a flexible, smooth,metallic or non-metallic intermediate section. Although the secondflexible member 282 is depicted as a tightly coiled spring in FIG. 1A,other structures capable of providing flexibility similar to the tightlycoiled spring depicted in FIG. 1A may be freely substituted.

The bushing 284 may be fabricated using any material or combination ofmaterials capable of engaging the external surface of the secondflexible member 282. In some embodiments, the bushing 284 is axiallydisplaceable along the external surface of the second flexible member282. In at least some implementations, the bushing 284 may threadedlyengage the external surface of the second flexible member 282.

The diameter of the bushing 284 is less than the diameter of the hollowcylindrical member 230. In embodiments, the bushing 284 may befabricated, in whole or in part, using a metallic material demonstratingadequate corrosion resistance in the expected operating environment.Example metallic materials include but are not limited to: brass,bronze, stainless steel, and similar. In other embodiments, the bushing284 may be fabricated, in whole or in part, using a non-metallicmaterial. Example non-metallic materials include but are not limited to:polypropylene, EPDM, polyoxymethylene (Delrin®), PVC, CPVC, fiberreinforced plastic (FRP), carbon fiber, or combinations thereof. Inembodiments, the bushing 284 may include a metallic member that iscoated with one or more non-metallic materials.

The coupling assembly 190 is affixed to detachably attached to thesecond end of the flexible shaft 110. The coupling assembly 190 includesa resilient ring 194 that prevents the coupling assembly 190 fromscraping against the walls of the lateral pipeline when the pipelinereinstatement tool 100 is inserted or withdrawn from the lateralpipeline. The coupling assembly includes a plurality of attachmentdevices, such as threaded attachment devices 192A-192 n that couple thecoupling assembly to the second end of the flexible shaft 110 to arotating shaft powered by one or more external devices.

FIG. 3A is an plan view of an illustrative pipeline reinstatement tool300 that includes a flexible shaft 110 having a first end and a secondend, a cutting head 120 affixed to the first end of the flexible shaft110, a sleeve 310 at least partially covering the cutting head 120, afirst flexible sleeve 140, a second flexible sleeve 180, a compressibletensioner 160 disposed between the first flexible sleeve 140 and thesecond flexible sleeve 180, and a coupling assembly 190 disposedproximate the second end of the flexible shaft 110, in accordance withat least one embodiment described herein. FIGS. 3B and 3C providecross-sections of the pipeline reinstatement tool 300 at the respectivepoints indicated in FIG. 3A. As depicted in FIG. 3A, in embodiments, asleeve 310 includes a second hollow cylindrical member having an openfirst end and a closed second end. The closed second end of the sleeve310 has an aperture formed therethrough to permit the passage of theflexible shaft 110 through the bit sleeve and into the aperture 238formed in the attachment member 236 of the cutting head 120. Theaperture formed in the second end of the sleeve 310 permits the axialdisplacement of the sleeve 310 along the flexible shaft 110.

Referring first to FIGS. 3A and 3B, beneficially, the thickness of thesleeve 310 exceeds the projection of the teeth 122 on the cutting head120, minimizes the likelihood that the teeth 122 contacting the surfaceof the lateral pipeline as the cutting head 120 is rotated against theliner in the reinstated pipeline. In addition, the force applied to thepipeline reinstatement tool 100 when penetrating the liner in thereinstated pipeline, compresses the compressible tensioner 160, allowingthe sleeve 310 to move (or be displaced) away from the first end of theflexible shaft 110, increasing the exposure of the cutting head 120 tothe liner in the reinstated pipeline. Thus, the sleeve 310 beneficiallyprotects the lateral pipeline from damage caused by the cutting head 120while being easily displaced to permit strong contact between thecutting head 120 and the liner in a reinstated pipeline. In embodiments,the closed second end of the bit sleeve may be chamfered, tapered, orotherwise sloped to permit the passage of the sleeve 310 and cuttinghead 120 after the cutting head 120 penetrates the liner in thereinstated pipeline 110.

Referring next to FIGS. 3A and 3C, in embodiments, one or more of thefixed spacer elements 244A may be disposed about the external surface ofthe self-adjusting alignment bushing 250A. In some embodiments, thefixed spacer element 244 may be formed integral with the self-adjustingalignment bushing 250A, for example the fixed spacer element 244 may becast integral with a metallic or non-metallic self-adjusting alignmentbushing 250A. In other embodiments, the fixed spacer element 244 may beseparately formed and affixed to the external surface of theself-adjusting alignment bushing 250A via one or more fasteners,chemical adhesives, thermal bonding, compression fitting, orcombinations thereof.

The pipeline reinstatement tool 300 includes a second flexible sleeve180 that includes a bushing 284 and a compressible element 320. Asdepicted in FIG. 3A, in some implementations, the compressible element320 may include a helical coil spring. The compressible element 320 mayinclude a helical coil spring having any number of turns. Thecompressible element 320 may have a spring constant of about: 2pounds/inch (lb/in) or less; 3 lb/in or less; 5 lb/in or less; 7 lb/inor less; 9 lb/in or less; 11 lb/in or less; 15 lb/in or less; 20 lb/inor less; or 25 lb/in or less. The compressible element 320 may include ahelical coil spring that includes: 5 useable turns or less; 10 useableturns or less; or 20 useable turns or less. The compressible element 320may include a helical coil spring have an uncompressed length of about:10% or less; 20% or less; 30% or less; 40% or less; 50% or less; or 60%or less of the length of the flexible shaft 110. The compressibleelement 320 may include a helical coil spring formed using wire having adiameter of: about 0.025 inches or less; about 0.050 inches or less;about 0.115 inches or less; or about 0.250 inches or less. Thecompressible element 320 may be fabricated using any metallic ornon-metallic material. Examples of such materials include, but are notlimited to: stainless steel, nickel, brass, carbon fiber, orcombinations thereof. The compressible element 320 beneficially providesadditional axial displacement along the flexible shaft 110 for thesleeve 310, the first flexible sleeve 140, and/or the compressibletensioner 160.

FIG. 4A is an plan view of an illustrative pipeline reinstatement tool400 that includes a flexible shaft 110 having a first end and a secondend, a cutting head 120 affixed to the first end of the flexible shaft,a plurality of resilient members 410A-410 n (collectively, “resilientmembers 410”) disposed about the cutting head 120, a hemisphericalfloating spacer element 420 a first flexible sleeve 140, a secondflexible sleeve 180, a spherical floating spacer element 430, acompressible tensioner 160 disposed between the first flexible sleeve140 and the second flexible sleeve 180, and a coupling assembly 190disposed proximate the second end of the flexible shaft 110, inaccordance with at least one embodiment described herein. FIGS. 4B and4C provide cross-sections of the pipeline reinstatement tool 400 at therespective points indicated in FIG. 4A. As depicted in FIG. 4A, inembodiments, the resilient members 410 may be disposed about theexternal surface of the hollow cylindrical element 230 and thehemispherical floating spacer element 420 may be disposed proximate thecutting head 120. In embodiments, the spherical floating spacer element430 is positioned between the first flexible sleeve 140 and thecompressible tensioner 160. In other embodiments (not depicted in FIG.4A) the spherical floating spacer element 430 is positioned between thecompressible tensioner 160 and the second flexible sleeve 180.

The resilient members 310 may include any number and or combination ofresilient or elastomeric members disposed proximate at least a portionof the external surface of the cutting head 120. The thickness of theresilient members 410 (i.e., the distance the resilient members 410project above the external surface of the cutting head 120) is greaterthan the projection of the teeth 122 from the external surface of thecutting head 120. The resilient members 410 may extend partially orcompletely about the external circumference of the cutting head 120.Where a plurality of resilient members 410 are used, each may have thesame or different thicknesses and/or cross-sectional profiles. Examplecross-sectional profiles include but are not limited to: circular (e.g.,a “O”-ring); rectangular; square; triangular; oval; or combinationsthereof. The resilient members 410 may be fabricated using one or morematerials demonstrating suitable corrosion and/or abrasion resistance.Example materials include but are not limited to: rubber, nitrile(Buna-N), ethylene propylene diene monomer (EPDM); Viton®; neoprene;polytetrafluoroethylene (PTFE—Teflon®); silicone; polyurethane; orcombinations thereof. The resilient members 410 beneficially minimizethe likelihood of contact between the teeth 122 and the sidewall of thelateral pipeline as the cutting head 120 rotates at speed. In operation,as the cutting head 120 penetrates the liner in the reinstated pipe, theresilient members 410 will tend to “roll” off the back (i.e., the secondend) of the cutting head 120.

Referring now to FIGS. 4A and 4B, the pipeline reinstatement tool 400includes a hemispherical floating spacer element 420 disposed proximatethe second end of the cutting head 120. The outside diameter 424 of thehemispherical floating spacer element 420 may be similar to the outsidediameter 235 of the hollow cylindrical shell 230. In embodiments, thehemispherical floating spacer element 320 may have an outside diameter324 similar to the outside diameter of the circular path of the teeth122 on the cutting head 120 (i.e., an outside diameter that is slightlylarger than the outside diameter of the hollow cylindrical member).

The hemispherical floating spacer element 420 may be fabricated usingany metallic, non-metallic, or composite material. Example metallicmaterials include but are not limited to: brass, bronze, stainlesssteel, or combinations thereof. Example non-metallic materials includebut are not limited to: Lexan®; polypropylene; polyethylene;polytetrafluoroethylene (PTFE—Teflon®); or combinations thereof. Anaperture 422 formed through the hemispherical floating spacer element420 permits the passage of the flexible shaft 110 through thehemispherical floating spacer element 420. The inside diameter of theaperture 422 is larger than the outside diameter of the flexible shaft110 thereby permitting the axial displacement of the hemisphericalfloating spacer element 420 along the flexible shaft 110.

Referring next to FIGS. 4A and 4C, the pipeline reinstatement tool 400includes a spherical floating spacer element 430 disposed proximate thecompressible tensioner 160. In embodiments, the spherical floatingspacer element 430 may be disposed between the first flexible sleeve 140and the compressible tensioner 160. In other embodiments, the sphericalfloating spacer element 430 may be disposed between the second flexiblesleeve 180 and the compressible tensioner 160. The outside diameter 434of the spherical floating spacer element 430 may be similar to theoutside diameter 235 of the hollow cylindrical shell 230. Inembodiments, the spherical floating spacer element 430 may have anoutside diameter 434 similar to the outside diameter of the circularpath of the teeth 122 on the cutting head 120 (i.e., an outside diameterthat is slightly larger than the outside diameter of the hollowcylindrical member). In other embodiments, the spherical floating spacerelement 430 may have an outside diameter 434 that is smaller or lessthan the outside diameter 235 of the hollow cylindrical member 230.

The spherical floating spacer element 430 may be fabricated using anymetallic, non-metallic, or composite material. Example metallicmaterials include but are not limited to: brass, bronze, stainlesssteel, or combinations thereof. Example non-metallic materials includebut are not limited to: Lexan®; polypropylene; polyethylene;polytetrafluoroethylene (PTFE—Teflon®); or combinations thereof. Anaperture 432 formed through the spherical floating spacer element 430permits the passage of the flexible shaft 110 through the sphericalfloating spacer element 430. The inside diameter of the aperture 432 islarger than the outside diameter of the flexible shaft 110 therebypermitting the axial displacement of the spherical floating spacerelement 430 along the flexible shaft 110.

FIG. 5A is an plan view of an illustrative pipeline reinstatement tool500 that includes a flexible shaft 110 having a first end and a secondend, a cutting head 120 affixed to the first end of the flexible shaft,a plurality of resilient members 410A-410 n (collectively, “resilientmembers 410”) disposed about the cutting head 120, and in which thefirst flexible sleeve 140 includes an external flexible member 510disposed at least partially about the first flexible member 242 and thesecond flexible sleeve 180 includes an external flexible member 520disposed at least partially about the second flexible member 282, inaccordance with at least one embodiment described herein. FIGS. 5B and5C provide cross-sections of the pipeline reinstatement tool 500 at therespective points indicated in FIG. 5A. As depicted in FIG. 5A, inembodiments, a first external flexible member 510 may be disposed aboutthe first flexible member 242 and a second external flexible member 520may be disposed about the second flexible member 282.

Referring first to FIGS. 5A and 5B, the first flexible sleeve 140includes the first flexible member 242 and a first external flexiblemember 510 disposed about at least a portion of the first flexiblemember 242. In embodiments, the first external flexible member 510encircles at least a portion of the axial length of the first flexiblemember 242. The first external flexible member 510 may enclose,encompass, or encircle about 10% or less; about 20% or less; about 30%or less; about 50% or less; or about 75% or less of the axial length ofthe first flexible member 242. In embodiments, the first flexible member242 may include a tightly coiled spring member and the first externalflexible member 510 may include a tightly coiled spring member having aninside diameter that closely matches the outside diameter of the firstflexible member 242. In such embodiments, the internal surface of thefirst external flexible member 510 may threadedly engage the externalsurface of the first flexible member 242. As the first flexible member242 is inserted into the first external flexible member 510, thestiffness of the first flexible sleeve 140 increases and as the firstflexible member 242 is withdrawn from the first external flexible member510, the stiffness of the first flexible sleeve 140 decreases.

Referring next to FIGS. 5A and 5C, the second flexible sleeve 180includes the second flexible member 282 and a second external flexiblemember 520 disposed about at least a portion of the second flexiblemember 282. In embodiments, the second external flexible member 520encircles at least a portion of the axial length of the second flexiblemember 282. The second external flexible member 520 may enclose,encompass, and/or encircle about 10% or less; about 20% or less; about30% or less; about 50% or less; or about 75% or less of the axial lengthof the second flexible member 282. In embodiments, the second flexiblemember 282 may include a tightly coiled spring member and the secondexternal flexible member 520 may include a tightly coiled spring memberhaving an inside diameter that closely matches the outside diameter ofthe second flexible member 282. In such embodiments, the internalsurface of the second external flexible member 520 may threadedly engagethe external surface of the second flexible member 282. As the secondflexible member 282 is inserted into the second external flexible member520, the stiffness of the second flexible sleeve 180 increases and asthe second flexible member 282 is withdrawn from the second externalflexible member 520, the stiffness of the second flexible sleeve 180decreases.

FIG. 6A is a plan view of an illustrative pipeline reinstatement tool600 in which the cutting head 120 includes one or more apertures formedin the hollow cylindrical shell 130, and in which the first flexiblemember 242 includes a first portion 242A and a second portion 242Bseparated by a floating spacer element 620, in accordance with at leastone embodiment described herein. FIGS. 6B, 6C, and 6D providecross-sections of the pipeline reinstatement tool 600 at the respectivepoints indicated in FIG. 6A. As depicted in FIG. 6A, one or more holesor apertures 610 may be formed in the hollow cylindrical member 230forming the cutting head 120. The presence of the one or more apertures610 beneficially permits material (e.g., liner material removed duringthe reinstatement process) trapped in the cutting head 120 to escape tothe area external to the cutting head 120. In embodiments, the one ormore apertures 610 may include a plurality of apertures having the sameor different diameters. The one or more apertures 610 may have adiameter of about 1/16 inch (in) or less; about ⅛ in or less; about ¼ inor less; about ⅜ in or less; about ½ in or less; or about ¾ in or less.As depicted in FIG. 6A, one or more elastomeric members 410 may bedisposed about the external surface of the cutting head 120 in locationsthat do not completely obstruct the one or more apertures 610.

As depicted in FIG. 6A, in embodiments, the first flexible sleeve 140includes a first floating spacer element 420 disposed proximate thecutting head 120. In addition the first flexible sleeve 140 isapportioned into a first flexible portion 242A and a second flexibleportion 242B separated by a second floating spacer element 620. Inembodiments, the first flexible portion 242A has a first length 243A(L1) and the second flexible portion 242B has a second length 243B. Inembodiments, the first length 243A and the second length 243B are equal.In other embodiments, the first length 243A and the second length 243Bare unequal. Referring to FIGS. 6A and 6B, the inside diameter of thefirst flexible sleeve 140 is greater than the outside diameter of theflexible shaft 110, thus the first flexible sleeve 140 is freelydisplaceable along the flexible shaft 110.

Referring next to FIGS. 6A and 6C, the pipeline reinstatement tool 600includes a toroidal floating spacer element 620 disposed between thefirst flexible portion 242A and the second flexible portion 242B of thefirst flexible sleeve 140. The outside diameter 624 of the toroidalfloating spacer element 620 may be similar to the outside diameter 235of the hollow cylindrical shell 230. In embodiments, the toroidalfloating spacer element 620 may have an outside diameter 624 similar tothe outside diameter of the circular path of the teeth 122 on thecutting head 120 (i.e., an outside diameter that is slightly larger thanthe outside diameter of the hollow cylindrical member 230). In otherembodiments, the toroidal floating spacer element 620 may have anoutside diameter 624 that is smaller or less than the outside diameter235 of the hollow cylindrical member 230.

The toroidal floating spacer element 620 may be fabricated using anymetallic, non-metallic, or composite material. Example metallicmaterials include but are not limited to: brass, bronze, stainlesssteel, or combinations thereof. Example non-metallic materials includebut are not limited to: Lexan®; polypropylene; polyethylene;polytetrafluoroethylene (PTFE—Teflon®); or combinations thereof. Anaperture 622 formed through the toroidal floating spacer element 620permits the passage of the flexible shaft 110 through the toroidalfloating spacer element 620. The inside diameter of the aperture 622 islarger than the outside diameter of the flexible shaft 110 therebypermitting the axial displacement of the toroidal floating spacerelement 620 along the flexible shaft 110.

FIG. 7A is a plan view of another illustrative pipeline reinstatementtool 700 in which the cutting head 120 includes a plurality of apertures610A-610 n formed in the hollow cylindrical shell 130, and in which thefirst flexible sleeve 140 includes a first external flexible member 710Aand a second external flexible member 710B disposed about at least aportion of the flexible member 242, in accordance with at least oneembodiment described herein. The pipeline reinstatement tool 700 furtherincludes an additional spacer element 720 disposed proximate thecoupling assembly 190. In embodiments, the spacer element 720 mayinclude a fixed spacer element affixed to either (or both) the couplingassembly 190 and the external drive shaft 114. In other embodiments, thespacer element 720 may include a floating spacer element able to moveaxially along the longitudinal axis of the external drive shaft 114.FIGS. 7B and 7C provide cross-sections of the pipeline reinstatementtool 700 at respective points along the first flexible sleeve 140 asindicated in FIG. 7A. FIG. 7D provides a cross-sectional view throughspacer element 720 of the pipeline reinstatement tool 700.

As depicted in FIG. 7A, a plurality of holes or apertures 610 may beformed in the hollow cylindrical member 230 portion of the cutting head120. The apertures 610A-610 n beneficially permit material (e.g., linermaterial removed during the reinstatement process) trapped in thecutting head 120 to escape to the region of the lateral pipelineexternal to the cutting head 120. Each of the plurality of apertures 610may have a diameter of about 1/16 inch (in) or less; about ⅛ in or less;about ¼ in or less; about ⅜ in or less; about ½ in or less; or about ¾in or less. As depicted in FIG. 7A, one or more elastomeric members 410may be disposed about the external surface 234 of the cutting head 120in locations that do not partially or completely obstruct the pluralityof apertures 610.

Referring now to FIGS. 7A, 7B, and 7C, the first flexible sleeve 140includes a first external flexible member 710A and a second externalflexible member 710B (collectively, “external flexible members 710”)disposed about at least a portion of the flexible member 242. Inembodiments, the first flexible member 242 may include a tightly coiledmember having an outside diameter and the external flexible members 710may include tightly coiled members having an inside diameter thatclosely matches the outside diameter of the first flexible member 242.In such embodiments, the external flexible members 710 may threadedlycouple to the first flexible member 242. Also, note that although onlytwo external flexible members 710 are depicted in FIG. 7A, any number ofexternal flexible members may be similarly positioned proximate all or aportion of the external surface of the first flexible member 242. Inembodiments, the external flexible members 710 may be affixed to theexternal surface of the first flexible member 242. In other embodiments,the external flexible members may be displaceable along the externalsurface of the first flexible member 242. As depicted in FIG. 7A, someor all of the external flexible members 710 may include a flared end toconform to the surface of the hemispherical floating spacer element 420and/or the spherical floating spacer element 430.

Referring next to FIGS. 7A and 7D, spacer element 720 may be disposedproximate the coupling assembly 190. In embodiments, the spacer element720 may be disposed about the external drive shaft 114 coupled to theflexible shaft 110 by the coupling assembly 190. In embodiments, thespacer element 720 may include a fixed spacer element affixed to either(or both) the coupling assembly 190 and/or the external drive shaft 114.In other embodiments, the spacer element 720 may include a floatingspacer element that can be axially displaced along the external driveshaft 114. The spacer element 720 beneficially minimizes the likelihoodof the coupling assembly 190 “hanging-up” in the lateral pipeline as thepipeline reinstatement tool 700 passes through the lateral pipeline.

The outside diameter 724 of spacer element 720 may be similar to theoutside diameter 235 of the hollow cylindrical shell 230. Inembodiments, the spacer element 720 may have an outside diameter 724similar to the outside diameter of the circular path of the teeth 122 onthe cutting head 120 (i.e., an outside diameter that is slightly largerthan the outside diameter of the hollow cylindrical member 230). Inother embodiments, the spacer element 720 may have an outside diameter724 that is smaller or less than the outside diameter 235 of the hollowcylindrical member 230. The spacer element 720 may be fabricated usingany metallic, non-metallic, or composite material. Example metallicmaterials include but are not limited to: brass, bronze, stainlesssteel, or combinations thereof. Example non-metallic materials includebut are not limited to: Lexan®; polypropylene; polyethylene;polytetrafluoroethylene (PTFE—Teflon®); or combinations thereof. Anaperture 722 formed through the spacer element 720 permits the passageof the external drive shaft 114 through spacer element 720.

FIG. 8A is a partial cross-sectional view of an illustrative pipelinereinstatement tool 200 disposed in a lateral pipeline 830, as thepipeline reinstatement tool 200 approaches a reinstated pipeline 810that includes a previously installed liner 820, in accordance with atleast one embodiment described herein. FIG. 8B is a partialcross-sectional view of the illustrative pipeline reinstatement tool 200of FIG. 8A after the pipeline reinstatement tool 200 has cut apenetration through the liner 820 to fluidly couple the lateral pipeline830 to the reinstated pipeline 810, in accordance with at least oneembodiment described herein. In embodiments, the reinstated pipeline 810may include any size pipeline formed using any material. For example,the diameter of the reinstated pipeline 810 may be about: 2 inches (in)or less; 3 in or less; 4 in or less; 6 in or less; 8 in or less; 12 inor less; 16 in or less; 18 in or less; or 24 in or less. The diameter ofthe lateral pipeline 830 may be about: 1 inch or less; 2 in or less; 3in or less; 4 in or less; 6 in or less; or 8 in or less.

The liner 820 may include any photo or thermally curable liner capableof in-situ installation within the pipeline 810. In embodiments, theliner 820 may include a curable resin impregnated fiberglass liner. Inembodiments, the liner 820 may be pulled through the pipeline 810 in aflattened state. Once in place, the liner 820 is “inflated” such thatthe liner 820 contacts the internal radius of the pipeline 810. Lateralpipelines 830 are blocked once the liner 820 is inflated to fill thepipeline 810. To restore drainage from the lateral pipeline 830, apenetration is made through the cured liner 820.

The lateral pipeline 830 may be fabricated using any of a number ofmaterials, such as polyvinyl chloride (PVC); chlorinated polyvinylchloride (CPVC); polyethylene; cast iron; carbon steel; galvanizedsteel; or combinations thereof. One may note that a number of thematerials listed for lateral pipelines 830 are relatively soft materialsthat may be easily damaged by the metal pipeline reinstatement tools orby the heat generated by the rotating shaft in current pipelinereinstatement tools as they slowly cut through the liner 820 within thereinstated pipeline 810. The pipeline reinstatement tools disclosedherein beneficially and advantageously include spacer elements tominimize the likelihood of the cutting head 120 contacting the sidewallof the lateral pipeline 830 or fittings disposed in the lateral pipeline830. In addition, the cutting head design disclosed herein minimizes thetime required to penetrate the liner 820 in the reinstated pipeline 810,reducing the heating that occurs in the lateral pipeline. Further, thespacers disposed on the pipeline reinstatement tools disclosed hereinmaintain a separation between the flexible shaft 110 and the sidewall ofthe lateral pipeline 830.

FIG. 9 is a rearward looking perspective view of the illustrativepipeline reinstatement tool 200 depicted in FIG. 2, in accordance withat least one embodiment described herein. FIG. 10 is a forward-lookingperspective view of the illustrative pipeline reinstatement tool 200depicted in FIG. 2, in accordance with at least one embodiment describedherein. Evident in FIGS. 9 and 10 is the protection provided to the highrotational speed flexible shaft 110 by the first flexible sleeve 140,second flexible sleeve 180, and compressible tensioner 160. Spacersdisposed along the length of the pipeline reinstatement tool 900minimize the possibility that the sleeve portions 140, 180 that mayexperience a degree of heating due to friction from contacting therotating flexible shaft 110 can contact the internal surfaces of thelateral pipeline 830. The spacers disposed along the length of thepipeline reinstatement tool 200 also minimize the likelihood that thecutting teeth 122 on the cutting head 120 will contact the internalsurface of the lateral pipeline 830—reducing the risk of unintendeddamage to the internal surfaces of the lateral pipeline.

FIG. 11A is a front elevation view of an illustrative cutting head 1100,in accordance with at least one embodiment described herein. FIG. 11B isa side elevation of the illustrative cutting head 1100, in accordancewith at least one embodiment described herein. FIG. 11C is a rearelevation view of the illustrative cutting head 1100, in accordance withat least one embodiment described herein. FIG. 11D is a rear perspectiveview of the illustrative cutting head 1100, in accordance with at leastone embodiment described herein. FIG. 11E is a front perspective view ofthe illustrative cutting head 1100, in accordance with at least oneembodiment described herein. FIG. 11F is a longitudinal cross-sectionalside view of the illustrative cutting head 1100, in accordance with atleast one embodiment described herein.

As depicted in FIGS. 11A-11F, the cutting head 1100 is formed as ahollow cylindrical member 230 having a first end 1110, a second end1120, an internal surface 232 and an external surface 234. An attachmentmember 236 is disposed transverse to the longitudinal axis 1150 of thecutting head 1100. Although the attachment member 236 is depicted as anannular member having a central aperture 238 sufficient in diameter topass the flexible shaft 110, in other embodiments, the attachment member110 may include a single bar or rectangular shaped member disposedtransverse to the longitudinal axis 1150 of the cutting head 1100. Inother embodiments, the attachment member 236 may include an “X” or crossshaped member disposed transverse to the longitudinal axis 1150 of thecutting head 1100. The attachment member 236 may be formed integral withthe hollow cylindrical member 230. The attachment member 236 may beformed separate from the hollow cylindrical member 230 and affixed tothe internal surface 232 of the hollow cylindrical member 230, forexample by welding, thermal bonding, chemical bonding, or compressionfitting. The attachment member 236 may be detachably attached to thehollow cylindrical member 230, for example using threaded fasteners,snap rings, or similar attachment devices.

An attachment sleeve 1130 may be affixed to the attachment member 236.In embodiments, the attachment sleeve 1130 may include a hollowcylindrical member having a central aperture sufficient to permit thepassage of the flexible shaft 110 therethrough. A plurality of shaftfasteners 1132 are disposed radially about the attachment sleeve 1130.The shaft fasteners detachably attach the cutting head 1100 to theflexible shaft 110. In at least some embodiments, the shaft fasteners1132 may include set screws or similar threaded fasteners disposedradially about the attachment sleeve 1130 at equal angles (e.g., 3fasteners 254 at 120°) or unequal angles (e.g., 3 shaft fasteners, thefirst two positioned at 90° with respect to each other, the thirdpositioned at 135° with respect to each of the first two).

FIG. 12A is a block diagram of an illustrative first flexible sleeve140, in accordance with at least one embodiment described herein. FIG.12B is an elevation of an illustrative flexible sleeve 140, inaccordance with at least one embodiment described herein. FIG. 12C is aperspective view of an illustrative self-adjusting alignment bushing 250included in the first flexible sleeve 140, in accordance with at leastone embodiment described herein. FIG. 12D is a cross-sectional elevationof an illustrative first flexible sleeve 140, such as depicted in FIGS.12A and 12B, in accordance with at least one embodiment describedherein. As depicted in FIGS. 12A-12D, the first flexible sleeve 140includes a first self-adjusting alignment bushing 250A coupled to thefirst end of the first flexible member 242 and a second self-adjustingalignment bushing 250B coupled to the second end of the first flexiblemember 242. Any number of fixed spacer elements 244A-244 n and anynumber of floating spacer elements 246A-246 n are disposed along theexternal surface of the first flexible member 242.

In embodiments, the self-adjusting alignment bushings 250 may be affixedto the first end and the second end of the first flexible member 242such that the self-adjusting alignment bushings 250 are in fixedlocations with respect to the longitudinal axis of the first flexiblemember 242. In other embodiments, the self-adjusting alignment bushings250 may be threadedly coupled to or threadedly engage the externalsurface of the first flexible member 242 such that the longitudinalposition of each self-adjusting alignment bushing 250A, 250B is variablewith respect to the first flexible member 242. A depicted in FIGS. 12B,12C, and 12D at least a portion of the internal surface of eachself-adjusting alignment bushing 250 may be threaded (i.e., containfemale threads) to accept the threaded insertion of the first flexiblemember 242. As depicted in FIG. 12D, an aperture 256A, 256B is formed ineach of the self-adjusting alignment bushings 250 to permit the freepassage of the flexible shaft 110 therethrough. Thus, the first flexiblesleeve 140 is freely displaceable along the longitudinal axis of theflexible shaft 110. The first flexible sleeve 140 may have any axiallength 1230 or diameter 1240 determined at least in part based on thediameter and/or size of the pipeline reinstatement tool 100. Inembodiments, the first flexible sleeve 140 may have an axial length 1230(i.e., a length measured along the longitudinal axis 112 of the flexibleshaft 110) of: about 4 inches (in) or less; about 6 in or less; about 8in or less; about 12 in or less; about 16 in or less; about 24 in orless; or about 36 in or less.

FIG. 13A is a side elevation of an illustrative compressible tensioner160, in accordance with at least one embodiment described herein. FIG.13B is a cross-sectional elevation of the illustrative compressibletensioner 160, in accordance with at least one embodiment describedherein. As depicted in FIGS. 13A and 13B, the compressible tensioner 160includes a first annular connector 270 coupled to the first end 1310 ofthe compressible element 262 and a second annular connector coupled tothe second end 1320 of the compressible element 262. Although thecompressible element 262 is depicted as a helical coil spring in FIGS.13A and 13B, other reversibly compressible elements and/or structurescapable of providing free passage to the flexible shaft 110 may besubstituted. In embodiments, the annular connectors 270A, 270B areaffixed to the first end 1310 and second end 1320 of the compressibleelement 262, respectively. In other embodiments, the annular connectors270A and 270B are detachably attached to the first end 1310 and secondend 1320 of the compressible element 262, respectively.

As depicted in FIG. 13B, an aperture 272A and 272B is formed in each ofthe annular connectors 270A and 270B, respectively. The diameter of theapertures 272A, 272B permits the free passage of the flexible shaft 110through the respective annular connector 270. Thus, the compressibletensioner 160 is freely displaceable along the longitudinal axis of theflexible shaft 110. The compressible tensioner 160 may have any axiallength 1330 or diameter 1340 determined at least in part based on thediameter and/or size of the pipeline reinstatement tool 100. Inembodiments, the compressible tensioner may have an axial length 1330(along the longitudinal axis 112) of: about 2 inches (in) or less; about3 in or less; about 4 in or less; about 6 in or less; about 8 in orless; about 10 in or less; or about 12 in or less. In embodiments, theaxial length 1330 of the compressible tensioner 160 is less than theaxial length of the first flexible sleeve 140. In embodiments, the axiallength of the compressible tensioner 160 is less than the axial lengthof the second flexible sleeve 180. In other embodiments, the axiallength of the compressible tensioner 160 is greater than the axiallength of the second flexible sleeve 180.

FIG. 14A is a side elevation of an illustrative second flexible sleeve180, in accordance with at least one embodiment described herein. FIG.14B is a cross-sectional elevation of the illustrative second flexiblesleeve 180, in accordance with at least one embodiment described herein.As depicted in FIGS. 14A and 14B, the second flexible sleeve 180includes a self-adjusting alignment bushing 284 coupled to the first end1410 of the second flexible member 282. In embodiments, the second end1420 of the second flexible member 282 is disposed proximate thecoupling assembly 190 (not shown in FIGS. 14A and 14B). In embodiments,the self-adjusting alignment bushing 284 is affixed to the first end1410 of the second flexible member 282. In other embodiments, theself-adjusting alignment bushing 284 is detachably attached to the firstend 1410 of the second flexible member 282. In at least someembodiments, threads 1450 formed or otherwise disposed in, on, or aboutat least a portion of the internal surface of the self-adjustingalignment bushing 284 may threadedly engage at least a portion of theexternal surface of the second flexible member 282.

As depicted in FIG. 14B, an aperture 286 is formed in the self-adjustingalignment bushing 284. The diameter of the aperture 286 permits the freepassage of the flexible shaft 110 through the respective self-adjustingalignment bushing 284. Thus, the second flexible sleeve 180 is freelydisplaceable along the longitudinal axis 112 of the flexible shaft 110.The second flexible sleeve 180 may have any axial length 1430 ordiameter 1440 determined at least in part based on the diameter and/orsize of the pipeline reinstatement tool 100. In embodiments, the secondflexible sleeve 180 may have an axial length 1430 that is less than theaxial length 1230 of the first flexible sleeve 1230. In embodiments, thelength 1430 of the second flexible sleeve 180 is about: about 10% orless; about 20% or less; about 30% or less; about 40% or less; about 50%or less; about 60% or less; about 70% or less; about 80% or less; orabout 90% or less of the axial length 1230 of the first flexible sleeve140. Although no fixed spacer elements 244 or floating spacer elements246 are depicted as being disposed about the second flexible member 282in FIGS. 14A and 14B, any number and/or combination of fixed spacerelements 244 and floating spacer elements 246 may be disposed about allor a portion of the external surface of the second flexible member 282.

FIG. 15A is a side elevation view of an illustrative cutting head 1500that includes an attachment member 236 having a plurality of apertures1510A-1510 n (collectively, “attachment member apertures 1510”) formedtherethrough, in accordance with at least one embodiment describedherein. FIG. 15B is a rear elevation of the illustrative cutting head1500 depicted in FIG. 15A, in accordance with at least one embodimentdescribed herein. FIG. 15C is a front elevation view of the illustrativecutting head 1500 depicted in FIG. 15A, in accordance with at least oneembodiment described herein.

As depicted in FIGS. 15A-15C, the cutting head 1500 is formed as ahollow cylindrical member 230 having a first end 1110, a second end1120, an internal surface 232 and an external surface 234. An attachmentmember 236 is disposed transverse to the longitudinal axis of thecutting head 1500. The attachment member 236 includes a central aperture238 sufficient in diameter to pass the flexible shaft 110. Inembodiments, a plurality of attachment member apertures 1510 are formedthrough the attachment member 236. The attachment member apertures 1510beneficially permit the passage of debris, detritus, and other materialsthrough the cutting head 1500 as contact is maintained between thecutting head 1500 and the liner 820 disposed in the reinstated pipeline810. The attachment member 236 may be formed integral with the hollowcylindrical member 230. The attachment member 236 may be formed separatefrom the hollow cylindrical member 230 and affixed to the internalsurface 232 of the hollow cylindrical member 230, for example bywelding, thermal bonding, chemical bonding, or compression fitting. Theattachment member 236 may be detachably attached to the hollowcylindrical member 230, for example using threaded fasteners, snaprings, or similar attachment devices.

An attachment sleeve 1130 may be affixed to the attachment member 236.In embodiments, the attachment sleeve 1130 may include a hollowcylindrical member having a central aperture sufficient to permit thepassage of the flexible shaft 110 therethrough. A plurality of shaftfasteners 1132 are disposed radially about the attachment sleeve 1130.The shaft fasteners detachably attach the cutting head 1100 to theflexible shaft 110. In at least some embodiments, the shaft fasteners1132 may include set screws or similar threaded fasteners disposedradially about the attachment sleeve 1100 at equal angles (e.g., 3fasteners 254 at 120°) or unequal angles (e.g., 3 shaft fasteners, thefirst two positioned at 90° with respect to each other, the thirdpositioned at 135° with respect to each of the first two).

FIG. 16A depicts a side elevation view of an illustrative two-piececutting head system 1600 that includes a cutting head 120 that isseparated from and slideably insertable into a hemispherical floatingspacer member 1610 that is slideably displaceable along the longitudinalaxis 112 of the flexible shaft 110, in accordance with at least oneembodiment described herein. FIG. 16B depicts a side elevation view ofthe illustrative two-piece cutting head 1600 as depicted in FIG. 16A inan assembled state, with the cutting head 120 inserted into thehemispherical floating spacer member 1610, in accordance with at leastone embodiment described herein. FIG. 16C depicts a front-elevation viewof the illustrative assembled two-piece cutting head 1600 as depicted inFIG. 16B, in accordance with at least one embodiment described herein.FIG. 16D is a cross-sectional elevation of the illustrative assembledtwo-piece cutting head 1600 as depicted in FIG. 16C along sectional line16D-16D, in accordance with at least one embodiment described herein.FIG. 16E depicts a rear-elevation view of the illustrative assembledtwo-piece cutting head 1600 as depicted in FIG. 16B, in accordance withat least one embodiment described herein. FIG. 16F depicts a sideelevation of an illustrative pipeline reinstatement tool that includesthe illustrative two-piece cutting head 1600 depicted in FIGS. 16A-16E,in accordance with at least one embodiment described herein.

As depicted in FIGS. 16A-16E. in embodiments, the cutting head 120 maybe slideably insertable in a cavity formed in a hemispherical floatingspacer element 1610. In operation, a force is applied along thelongitudinal axis 112 of the flexible member 110, the hemisphericalfloating spacer element 1610 may be displaced along the flexible member,exposing the cutting head 120. In embodiments, the cavity formed in thehemispherical floating spacer element 1610 may include a plurality ofportions, such as a first portion 1612 to accommodate the slideableinsertion of the cylindrical member 230, a second portion 1614 coupledto the first portion 1612 to accommodate the slideable insertion of theattachment sleeve 1130, and a third portion 1616 coupled to the secondportion 1614 having an aperture 1618 formed therethrough to permit thepassage of the flexible shaft 110.

The hemispherical floating spacer element 1610 may have any outsidediameter. In embodiments, the diameter of the hemispherical floatingspacer element 1610 may be selected or otherwise determined based on thediameter of the lateral pipeline 830 through which the pipelinereinstatement tool passes to reach the reinstated pipeline 810. Inembodiments, the hemispherical floating spacer element 1610 may have adiameter of: between ¼ inch (in) and 1.00 in; 1 1/16 in and 2.00 in; 21/16 in and 3.00 in; 3 1/16 in and 4.00 in; 4 1/16 in and 5.00 in; or 51/16 in and 6.00 in.

The hemispherical floating spacer element 1610 may be fabricated usingany metallic, non-metallic, or composite material. Example metallicmaterials include but are not limited to: brass, bronze, stainlesssteel, or combinations thereof. Example non-metallic materials includebut are not limited to: Lexan®; polypropylene; polyethylene;polytetrafluoroethylene (PTFE—Teflon®); or combinations thereof. Anaperture 1618 formed through the hemispherical floating spacer element1610 permits the passage of the flexible shaft 110 through thehemispherical floating spacer element 1610. The inside diameter of theaperture 1618 is larger than the outside diameter of the flexible shaft110 thereby permitting the axial displacement of the hemisphericalfloating spacer element 1610 along the flexible shaft 110.

The two-piece cutting head system 1600 includes a cutting head 120having a plurality of cutting teeth 122A-122 n. In embodiments, theouter edge of each of the cutting teeth 122 is flush with the externalsurface 234 of the hollow cylindrical member 230 (i.e., the outsidediameter of the circle formed by the cutting teeth 122 is identical toor slightly smaller than the outside diameter of the hollow cylindricalmember 230). In such embodiments, the cutting head, including all or aportion of each of the plurality of cutting teeth 122 may be slideablyinserted to the cavity formed in the hemispherical floating spacerelement 1610. Although six (6) cutting teeth are depicted in FIGS.16A-16E, the cutting head 120 included in the system 1600 may includeany number of symmetrically or asymmetrically disposed cutting teeth122. Although the cutting teeth 122 are depicted as having a similartriangular or pyramidal cutting edge, in embodiments some or all of thecutting teeth 122 may have the same or different cutting profiles.

As depicted in FIGS. 16A-16E, in embodiments, the cutting head 120 mayinclude a button removal feature 1620 disposed at least partially withinthe hollow cylindrical member 230. As depicted in FIGS. 16A-16E, thebutton removal feature 1620 may include a pyramidal or stepped pyramidalblade feature intended to beneficially damage or reduce the size of therigid liner “button” removed by the two-piece cutting head system 1600from the liner 820 within the reinstated pipeline 810 thereby easing theflushing of the “button” from the reinstated pipeline 810. The cuttinghead 120 includes an attachment member 236 having a plurality ofapertures 1510A-1510D formed therethrough.

As depicted in FIGS. 16A-16E, the cutting head 120 is formed as a hollowcylindrical member 230 having a first end 1110, a second end 1120, aninternal surface 232 and an external surface 234. An attachment member236 is disposed transverse to the longitudinal axis of the cutting head1500. The attachment member 236 includes a central aperture 238sufficient in diameter to pass the flexible shaft 110. In embodiments, aplurality of attachment member apertures 1510 are formed through theattachment member 236. The attachment member apertures 1510 beneficiallypermit the passage of debris, detritus, and other materials through thecutting head 120 as contact is maintained between the cutting head 1500and the liner 820 disposed in the reinstated pipeline 810. Theattachment member 236 may be formed integral with the hollow cylindricalmember 230. The attachment member 236 may be formed separate from thehollow cylindrical member 230 and affixed to the internal surface 232 ofthe hollow cylindrical member 230, for example by welding, thermalbonding, chemical bonding, or compression fitting. The attachment member236 may be detachably attached to the hollow cylindrical member 230, forexample using threaded fasteners, snap rings, or similar attachmentdevices.

An attachment sleeve 1130 may be affixed to the attachment member 236.In embodiments, the attachment sleeve 1130 may include a hollowcylindrical member having a central aperture sufficient to permit thepassage of the flexible shaft 110 therethrough. A plurality of shaftfasteners 1132 are disposed radially about the attachment sleeve 1130.The shaft fasteners detachably attach the cutting head 1100 to theflexible shaft 110. In at least some embodiments, the shaft fasteners1132 may include set screws or similar threaded fasteners disposedradially about the attachment sleeve 1100 at equal angles (e.g., 3fasteners each at 120° with respect to the other fasteners) or unequalangles (e.g., 3 shaft fasteners, the first two positioned at 90° withrespect to each other, the third positioned at 135° with respect to eachof the first two).

Finally referring to FIG. 16F, in operation, as a longitudinal force isapplied along the flexible shaft 110, the compressible member 262included in the compressible tensioner 160 and/or the compressiblemember 320 included in second flexible sleeve 320 are compressed,allowing a displacement of the floating spacer element 1610 along theflexible shaft 110. Since the cutting head 120 is affixed to theflexible shaft 110, as the floating spacer element 1610 is displacedalong the flexible shaft 110, the cutting head is exposed, therebyallowing the cutting head to penetrate the liner 820 within thereinstated pipeline 810.

FIG. 17A depicts a side elevation view of an illustrative dual-bladecutting head system 1700 that includes a second cutting head 1710disposed coaxially with and at least partially within the first cuttinghead 120, such that the dual-blade cutting head formed by the firstcutting head 120 and the second cutting head 1710 are slideablyinsertable into a hemispherical floating spacer member 1610 that isslideably displaceable along the longitudinal axis 112 of the flexibleshaft 110, in accordance with at least one embodiment described herein.FIG. 17B depicts a side elevation view of the illustrative dual-bladecutting head 1700 as depicted in FIG. 17A in an assembled state, withthe first cutting head 120 affixed to the second cutting head 1710 andinserted into the hemispherical floating spacer member 1610, inaccordance with at least one embodiment described herein. FIG. 17Cdepicts a front-elevation view of the illustrative assembled dual-bladecutting head 1700 as depicted in FIG. 17B, in accordance with at leastone embodiment described herein. FIG. 17D is a cross-sectional elevationof the illustrative assembled dual-blade cutting head 1700 as depictedin FIG. 17C along sectional line 17D-17D, in accordance with at leastone embodiment described herein. FIG. 17E depicts a rear-elevation viewof the illustrative assembled dual-blade cutting head 1700 as depictedin FIG. 17B, in accordance with at least one embodiment describedherein. FIG. 17F depicts a side elevation of an illustrative pipelinereinstatement tool that includes the illustrative dual-blade cuttinghead 1700 depicted in FIGS. 17A-17E, in accordance with at least oneembodiment described herein.

As depicted in FIGS. 17A-17E, in embodiments, the dual-blade cuttinghead system 1700 includes a first cutting head 120 having a plurality ofcutting teeth 122A-122 n and a second cutting head 1710 having a secondplurality of cutting teeth 1722A-1722 n. In embodiments, the secondcutting head 1710 is disposed at least partially within the hollowcylindrical member 230 forming the first cutting head 120. Inembodiments, the outside diameter of the second cutting head 1700 isless than the inside diameter of the first cutting head 120 such that agap 1750 exists between the outer surface 1734 of the second cuttinghead 1710 and the inner surface 232 of the first cutting head 120. Inembodiments, the second cutting head 1710 is affixed to the firstcutting head 120, for example, by welding, chemically bonding, orthermally boding at least a portion of the second cutting head 1710 tothe attachment member 236 of the first cutting head 120. As depicted inFIGS. 17A-17E, the second cutting head 1710 beneficially damages orreduces the size of the rigid liner “button” removed by the dual-bladecutting head system 1700 from the liner 820 within the reinstatedpipeline 810 thereby easing the flushing of the “button” from thereinstated pipeline 810. In embodiments, the plurality of cutting teeth122 on the first cutting head 120 may be coplanar with the secondplurality of cutting teeth 1722 on the second cutting head 1710. Inother embodiments, the plane of the second plurality of cutting teeth1722 may be positioned or recessed behind the plane of the plurality ofcutting teeth 122 on the first cutting head 120 (i.e., the plurality ofcutting teeth 122 may project beyond the second plurality of cuttingteeth 1722). In yet other embodiments, the plane of the plurality ofcutting teeth 122 on the first cutting head 120 may be positioned orrecessed behind the second plurality of cutting teeth 1722 on the secondcutting head 1710 (i.e., the second plurality of cutting teeth 1722 mayproject beyond the plurality of cutting teeth 122).

In embodiments, the outer edge of each of the cutting teeth 1722 isflush with the external surface 1734 of the second cutting head 1710(i.e., the outside diameter of the circle formed by the second pluralityof cutting teeth 1722 is identical to or slightly smaller than theoutside diameter of the second cutting head 1710). Although the secondplurality of cutting teeth 1722 includes eight (8) cutting teeth asdepicted in FIGS. 17A-17E, the second cutting head 1710 may include asecond plurality of cutting teeth 1722 having any number ofsymmetrically or asymmetrically disposed teeth. Although each of thesecond plurality of cutting teeth 1722 are depicted as having a similartriangular or pyramidal cutting edge, in embodiments, each of some orall of the second plurality of cutting teeth 1722 may have the same ordifferent cutting profiles.

As depicted in FIGS. 17A-17E, in some embodiments, a button removalfeature 1720 may be disposed at least partially within the secondcutting head 1710. As depicted in FIGS. 17A-17E, the button removalfeature 1720 may include a sharpened edge or blade feature thatdestroys, fractures, fragments, damages, or otherwise reduces the sizeand/or diameter of the rigid liner “button” removed from the liner 820by the dual-blade cutting head system 1700, thereby easing the flushingof the “button” from the reinstated pipeline 810. Although omitted fromFIGS. 17A-17E, in embodiments, the dual-blade cutting head 1700 mayinclude an attachment member having one or more apertures that fluidlyconnect the inner volume of the second cutting head 1710 with theexterior volume above the attachment member 236 of the first cuttinghead 120. In embodiments, the button removal feature 1720 may be formedintegral with the second cutting head 1710, for example via casting. Inother embodiments, the button removal feature 1720 may be separatelyformed and coupled, attached, or otherwise affixed to the internalsurface 1732 and/or second end of the second cutting head 1710.

As depicted in FIGS. 17A-17E, the second cutting head 1710 is formed asa hollow cylindrical member having a first end that includes the secondplurality of cutting teeth 1722, a second end disposed proximate theattachment member 236 of the first cutting head 120, an internal surface1732 and an external surface 1734. In embodiments, the second end of thesecond cutting head 1710 includes a central aperture sufficient indiameter to permit passage of the flexible shaft 110. In embodiments,the second end of the second cutting head 1722 may be permanentlyaffixed to the attachment member 236 of the first cutting head 120 viawelding, thermal bonding, chemical bonding, press-fitting, riveting, orsimilar. In embodiments, the second end of the second cutting head 1722may be detachably attached or coupled to the attachment member 236 ofthe first cutting head 120 via one or more threaded couplings, threadedfasteners, set screws, or similar.

Finally referring to FIG. 17F, in operation, as a longitudinal force isapplied along the flexible shaft 110, the compressible member 262included in the compressible tensioner 160 and/or the compressiblemember 320 included in second flexible sleeve 320 are compressed,allowing a displacement of the floating spacer element 1610 along theflexible shaft 110. Since the cutting head 120 is affixed to theflexible shaft 110, as the floating spacer element 1610 is displacedalong the flexible shaft 110, the cutting head is exposed, therebyallowing the cutting head to penetrate the liner 820 within thereinstated pipeline 810.

FIG. 18A depicts a side elevation view of an illustrative dual-bladecutting head system 1800 that includes a second cutting head 1710disposed coaxially with and at least partially within the first cuttinghead 120, such that the dual-blade cutting head formed by the firstcutting head 120 and the second cutting head 1710 are slideablyinsertable into a cylindrical floating spacer member 1810 that isslideably displaceable along the longitudinal axis 112 of the flexibleshaft 110, in accordance with at least one embodiment described herein.FIG. 18B depicts a side elevation view of the illustrative dual-bladecutting head 1800 as depicted in FIG. 18A in an assembled state, withthe first cutting head 120 affixed to the second cutting head 1710 andinserted into the cylindrical floating spacer member 1810, in accordancewith at least one embodiment described herein. FIG. 18C depicts afront-elevation view of the illustrative assembled dual-blade cuttinghead 1800 as depicted in FIG. 18B, in accordance with at least oneembodiment described herein. FIG. 18D is a cross-sectional elevation ofthe illustrative assembled dual-blade cutting head 1800 as depicted inFIG. 18C along sectional line 18D-18D, in accordance with at least oneembodiment described herein. FIG. 18E depicts a rear-elevation view ofthe illustrative assembled dual-blade cutting head 1800 as depicted inFIG. 18B, in accordance with at least one embodiment described herein.FIG. 18F depicts a side elevation of an illustrative pipelinereinstatement tool that includes the illustrative dual-blade cuttinghead 1800 depicted in FIGS. 18A-18E, in accordance with at least oneembodiment described herein.

As depicted in FIGS. 18A-18E. in embodiments, the cutting head 120 maybe slideably insertable in a cavity formed in a cylindrical floatingspacer element 1810. In operation, a force is applied along thelongitudinal axis 112 of the flexible member 110, the hemisphericalfloating spacer element 1610 may be displaced along the flexible member,compressing the compressible element 262 in the compressible tensioner160 and/or the compressible element 320 in the second flexible sleeve180, thereby exposing the cutting head 120. In embodiments, the cavityformed in the cylindrical floating spacer element 1810 may include aplurality of portions, such as a first portion 1812 to accommodate theslideable insertion of the cylindrical member 230, a second portion 1814coupled to the first portion 1812 to accommodate the slideable insertionof the attachment sleeve 1130, and a third portion 1816 coupled to thesecond portion 1614 having an aperture 1818 formed therethrough topermit the passage of the flexible shaft 110.

The cylindrical floating spacer element 1810 may have any outsidediameter. In embodiments, the diameter of the cylindrical floatingspacer element 1810 may be selected or otherwise determined based on thediameter of the lateral pipeline 830 through which the pipelinereinstatement tool passes to reach the reinstated pipeline 810. Inembodiments, the cylindrical floating spacer element 1810 may have adiameter of: between ¼ inch (in) and 1.00 in; 1 1/16 in and 2.00 in; 21/16 in and 3.00 in; 3 1/16 in and 4.00 in; 4 1/16 in and 5.00 in; or 51/16 in and 6.00 in.

The cylindrical floating spacer element 1810 may be fabricated using anymetallic, non-metallic, or composite material. Example metallicmaterials include but are not limited to: brass, bronze, stainlesssteel, or combinations thereof. Example non-metallic materials includebut are not limited to: Lexan®; polypropylene; polyethylene;polytetrafluoroethylene (PTFE—Teflon®); or combinations thereof. Anaperture 1818 formed through the cylindrical floating spacer element1810 permits the passage of the flexible shaft 110 through thecylindrical floating spacer element 1810. In embodiments, one or morebushings may be inserted into the aperture 1818 to accommodate the useof the cylindrical floating spacer element 1810 on different sizeflexible shafts 110. The inside diameter of the aperture 1818, and anybushings installed in the aperture 1818, is larger than the outsidediameter of the flexible shaft 110 thereby permitting the axialdisplacement of the cylindrical floating spacer element 1810 along theflexible shaft 110.

As depicted in FIGS. 18A-18E, in embodiments, the dual-blade cuttinghead system 1800 includes a first cutting head 120 having a plurality ofcutting teeth 122A-122 n and a second cutting head 1710 having a secondplurality of cutting teeth 1722A-1722 n. In embodiments, the secondcutting head 1710 is disposed at least partially within the hollowcylindrical member 230 forming the first cutting head 120. Inembodiments, the outside diameter of the second cutting head 1700 isless than the inside diameter of the first cutting head 120 such that agap 1750 exists between the outer surface 1734 of the second cuttinghead 1710 and the inner surface 232 of the first cutting head 120. Inembodiments, the second cutting head 1710 is affixed to the firstcutting head 120, for example, by welding, chemically bonding, and/orthermally boding at least a portion of the second cutting head 1710 tothe attachment member 236 of the first cutting head 120.

As depicted in FIGS. 18A-18E, the second cutting head 1710 beneficiallydamages or reduces the size of the rigid liner “button” removed by thedual-blade cutting head system 1800 from the liner 820 within thereinstated pipeline 810 thereby easing the flushing of the “button” fromthe reinstated pipeline 810. In embodiments, the plurality of cuttingteeth 122 on the first cutting head 120 may be coplanar with the secondplurality of cutting teeth 1722 on the second cutting head 1710. Inother embodiments, the plane of the second plurality of cutting teeth1722 may be positioned or recessed behind the plane of the plurality ofcutting teeth 122 on the first cutting head 120 (i.e., the plurality ofcutting teeth 122 may project beyond the second plurality of cuttingteeth 1722). In yet other embodiments, the plane of the plurality ofcutting teeth 122 on the first cutting head 120 may be positioned orrecessed behind the second plurality of cutting teeth 1722 on the secondcutting head 1710 (i.e., the second plurality of cutting teeth 1722 mayproject beyond the plurality of cutting teeth 122).

In embodiments, the outer edge of each of the cutting teeth 1722 isflush with the external surface 1734 of the second cutting head 1710(i.e., the outside diameter of the circle formed by the second pluralityof cutting teeth 1722 is identical to or slightly smaller than theoutside diameter of the second cutting head 1710). Although the secondplurality of cutting teeth 1722 includes eight (8) cutting teeth asdepicted in FIGS. 18A-18E, the second cutting head 1710 may include asecond plurality of cutting teeth 1722 having any number ofsymmetrically or asymmetrically disposed teeth. Although each of thesecond plurality of cutting teeth 1722 are depicted as having a similartriangular or pyramidal cutting edge, in embodiments, each of some orall of the second plurality of cutting teeth 1722 may have the same ordifferent cutting profiles.

As depicted in FIGS. 18A-18E, in some embodiments, a button removalfeature 1720 may be disposed at least partially within the secondcutting head 1710. As depicted in FIGS. 18A-18E, the button removalfeature 1720 may include a sharpened edge or blade feature thatdestroys, fractures, fragments, damages, or otherwise reduces the sizeand/or diameter of the rigid liner “button” removed from the liner 820by the dual-blade cutting head system 1700. Although omitted from FIGS.18A-18E, in embodiments, the dual-blade cutting head 1800 may include anattachment member having one or more apertures that fluidly connect theinner volume of the second cutting head 1710 with the exterior volumeabove the attachment member 236 of the first cutting head 120. Inembodiments, the button removal feature 1720 may be formed integral withthe second cutting head 1710, for example via casting. In otherembodiments, the button removal feature 1720 may be separately formedand coupled, attached, or otherwise affixed to the internal surface 1732and/or second end of the second cutting head 1710.

As depicted in FIGS. 18A-18E, the second cutting head 1710 is formed asa hollow cylindrical member having a first end that includes the secondplurality of cutting teeth 1722, a second end disposed proximate theattachment member 236 of the first cutting head 120, an internal surface1732 and an external surface 1734. In embodiments, the second end of thesecond cutting head 1710 includes a central aperture sufficient indiameter to permit passage of the flexible shaft 110. In embodiments,the second end of the second cutting head 1722 may be permanentlyaffixed to the attachment member 236 of the first cutting head 120 viawelding, thermal bonding, chemical bonding, press-fitting, riveting, orsimilar. In embodiments, the second end of the second cutting head 1722may be detachably attached or coupled to the attachment member 236 ofthe first cutting head 120 via one or more threaded couplings, threadedfasteners, set screws, or similar.

Finally referring to FIG. 18F, the pipeline reinstatement tool mayinclude a cylindrical floating spacer element 1820 disposed between thefirst flexible sleeve 140 and the second flexible sleeve 180. In otherembodiments, the cylindrical floating spacer element 1820 may bedisposed between the first flexible sleeve 140 and the compressibletensioner 160. In yet other embodiments, the spherical floating spacerelement 430 may be disposed between the second flexible sleeve 180 andthe compressible tensioner 160. The outside diameter of the cylindricalfloating spacer element 1820 may be similar to the outside diameter ofthe cylindrical spacer element 1810 disposed about the dual-bladecutting head 1800. In other embodiments, the cylindrical floating spacerelement 1820 may have an outside diameter similar to the outsidediameter of the circular path of the teeth 122 on the first cutting head120. In yet other embodiments, the cylindrical floating spacer element1820 may have an outside diameter that is smaller or less than theoutside diameter 235 of the hollow cylindrical member 230 forming thefirst cutting head 120.

The spherical floating spacer element 1820 may be fabricated using anymetallic, non-metallic, or composite material. Example metallicmaterials include but are not limited to: brass, bronze, stainlesssteel, or combinations thereof. Example non-metallic materials includebut are not limited to: Lexan®; polypropylene; polyethylene;polytetrafluoroethylene (PTFE—Teflon®); or combinations thereof. Anaperture formed through the cylindrical floating spacer element 1820permits the passage of the flexible shaft 110 through the cylindricalfloating spacer element 1820. The inside diameter of the aperture islarger than the outside diameter of the flexible shaft 110 therebypermitting the axial displacement of the cylindrical floating spacerelement 1820 along the flexible shaft 110.

In operation, as a longitudinal force is applied along the flexibleshaft 110 compresses the compressible member 262 included in thecompressible tensioner 160 and/or the compressible member 320 includedin second flexible sleeve 320, thereby allowing a displacement of thefloating spacer element 1810 along the flexible shaft 110. Since thecutting head 120 is affixed to the flexible shaft 110, as the floatingspacer element 1810 is displaced along the flexible shaft 110, thecutting head is exposed, thereby allowing the cutting head to penetratethe liner 820 within the reinstated pipeline 810.

FIG. 19A depicts an illustrative pipeline reinstatement tool 1900 inwhich the compressible tensioner 160 and the second flexible sleeve 180have been combined to provide compressible tensioner sleeve 1910, inaccordance with at least one embodiment described herein. FIG. 19Bdepicts the illustrative pipeline reinstatement tool 1900 depicted inFIG. 19A with an axially applied force (“F”) 1930 causing the dual-bladecutting head to project from the cylindrical floating spacer element1810, exposing the first cutter head 120 and the second cutter head1710, in accordance with at least one embodiment described herein.

Referring first to FIG. 19A, the compressible tensioner sleeve 1910includes a compressible element 1912 that may have a fixed or variablespring rate (e.g., where the compressible element comprises a helicalcoil spring, the coils may be evenly or unevenly spaced). In the absenceof the axially applied force 1930 the compressible elements 1912 has arelatively longer first length (L₁) 1940.

Referring next to FIG. 19B, as the axial force 1930 is applied along theflexible shaft, the compressible member 1912 compresses to a relativelyshorter second length (L₂) 1950. The reduction in length of thecompressible member 1912 permits the displacement of the cylindricalfloating spacer element 1810, the first flexible sleeve 140, and thecylindrical floating spacer element 1820 along the flexible shaft 110.The displacement of the cylindrical floating spacer element 1810 exposesthe first cutter head 120 and the second cutter head 1710 allowing thepipeline reinstatement tool 1900 to penetrate the liner 820 in areinstated pipeline 810.

FIG. 20 is a side elevation view of an illustrative pipelinereinstatement tool 2000 that includes a flexible sleeve portion 140having a first cylindrical floating spacer element 1820A and a secondcylindrical floating spacer element 1820B disposed along the flexibleshaft 110 and positioned between a first compressible tensioner section160A and a second compressible tensioner section 160B, in accordancewith at least one embodiment described herein. FIG. 20A is a sectionalview of the illustrative pipeline reinstatement tool depicted in FIG. 20along sectional line 20A-20A, in accordance with at least one embodimentdescribed herein. FIG. 20B is a sectional view of the illustrativepipeline reinstatement tool depicted in FIG. 20 along sectional line20B-20B, in accordance with at least one embodiment described herein.FIG. 20C is a sectional view of the illustrative pipeline reinstatementtool depicted in FIG. 20 along sectional line 20C-20C, in accordancewith at least one embodiment described herein. FIG. 20D is a sectionalview of the illustrative pipeline reinstatement tool depicted in FIG. 20along sectional line 20D-20D, in accordance with at least one embodimentdescribed herein.

As depicted in FIG. 20, the flexible sleeve portion 140 includes aflexible member 242 disposed about the flexible shaft 110 and positionedbetween the first cylindrical floating spacer element 1820A and thesecond cylindrical floating spacer element 1820B. Also as depicted inFIG. 20, the first compressible tensioner section 160A may include afirst compressible element 262A positioned between a first annularconnector 270A and an intermediate annular connector 270B and a secondcompressible element 262B positioned between the intermediate annularconnector 270B and a second annular connector 270C. The secondcompressible tensioner section 160B includes a compressible element 262Cdisposed between a third annular connector 270D and a fourth annularconnector 270E. In embodiments, the length (L₁) of the firstcompressible tensioner section 160A may be greater than the length (L₂)of the second compressible tensioner section 160B.

The flexible sleeve portion 140 includes the first cylindrical floatingspacer element 1820A and the second cylindrical floating spacer element1820B. The first cylindrical floating spacer element 1820A and thesecond cylindrical floating spacer element 1820B may be longitudinallydisplaced along the axis of the flexible member 110. In embodiments, theflexible member 242 may include a tightly wound, incompressible, butflexible helical coil spring as depicted in FIG. 20. In suchembodiments, the distance between the first cylindrical floating spacerelement 1820A and the second cylindrical floating spacer element 1820Bremains substantially fixed and permits the transmission of a forceapplied along the longitudinal axis of the flexible shaft to compresseither or both the first compressible tensioner section 160A and/or thesecond compressible tensioner section 160B to expose the cylindricalcutting head 1100.

The flexible sleeve portion 140 includes a flexible member 242positioned between the first cylindrical floating spacer element 1820Aand the second cylindrical floating spacer element 1820B such that afirst end of the flexible member 242 is positioned proximate the firstcylindrical floating spacer element 1820A and a second end of theflexible member 242 is positioned proximate the second cylindricalfloating spacer element 1820B. In embodiments, neither the first end northe second end of the flexible member 242 is flared. Thus, in someembodiments, the flexible member 242 may maintain a substantiallyconstant internal diameter and a substantially constant externaldiameter along the longitudinal length of the flexible member 242. Inother embodiments, either or both the first end and/or the second end ofthe flexible member 242 may have an increasing radius that causes therespective end to flare outward. In such embodiments, the flexiblemember 242 may have a variable internal diameter and external diameteralong at least a portion of the length of the flexible member 242. Insome embodiments, the surface of the first cylindrical floating spacerelement 1820A and/or the second cylindrical floating spacer element1820B may be radiused or curved proximate the first end and/or secondend of the flexible member 242. In such instances, the increasing radiusof the flexible member may approximate or be the same as the curvatureof the cylindrical floating spacer element, thereby providing anextended contact surface between the flexible member 242 and thecylindrical floating spacer element.

A first end of the first compressible element 262A seats inside a cavityor void space formed inside the first annular connector 270A and asecond end of the first compressible element 262A seats inside a cavityor void space formed inside a first end of the intermediate annularconnector 270B. Similarly, a first end of the second compressibleelement 262B seats inside a cavity or void space formed inside a secondend of the intermediate annular connector 270B and a second end of thesecond compressible element 262B seats inside a cavity or void spaceformed inside the second annular connector 270C.

In embodiments, the first end of the first compressible element 262A maybe physically affixed inside the cavity or void space inside the firstannular connector 270A. In embodiments, the first end of the firstcompressible element 262A may be press-fit, chemically bonded, and/orthermally welded inside the cavity or void space inside the firstannular connector 270A. In other embodiments, the first end of the firstcompressible element 262A may be detachably attached to the insidesurface of the cavity or void space inside the first annular connector270A. For example the first end of the first compressible element 262Amay be threadedly attached to the inside surface of the cavity or voidspace inside the first annular connector 270A.

The first compressible element 262A may include any number and/orcombination of metallic or non-metallic members capable of compressionalong the longitudinal axis 112 of the flexible member 110 uponapplication of a force applied along the longitudinal axis 112 of theflexible member 110. In embodiments, the first compressible element 262Aincludes a compressible element having a first spring constant (K₁)under compression. In embodiments, the first compressible element 262Aincludes a metallic helical coil spring having any number of turns. Inembodiments, the first compressible element 262A includes a metallichelical coil spring fabricated using one or more corrosion resistantmaterial such as, aluminum, stainless steel, galvanized steel, coatedsteel, nickel containing alloys, titanium, or combinations thereof. Theflexible shaft 110 passes through a central aperture formed in the firstcompressible element. The first compressible element 262A may include ahelical coil spring formed using round, square, or rectangular wirestock.

A first end of the intermediate annular connector 270B receives thesecond end of the first compressible element 262A and the opposed secondend of the intermediate annular connector 270B receives the first end ofthe second compressible element 262B. The second annular connector 270Creceives the second end of the second compressible element 262B. Thesecond annular connector 270C may be disposed proximate the firstcylindrical floating spacer element 1820A.

The second compressible element 262B may include any number and/orcombination of metallic or non-metallic members capable of compressionalong the longitudinal axis 112 of the flexible member 110 uponapplication of a force applied along the longitudinal axis 112 of theflexible member 110. In embodiments, the second compressible element262B includes a compressible element having a second spring constant(K₂) under compression. In embodiments, the second spring constant ofthe second compressible element 262B may be similar to the first springconstant of the first compressible element 262A. In other embodiments,the second spring constant of the second compressible element 262B maybe greater than the first spring constant of the first compressibleelement 262A. In yet other embodiments, the second spring constant ofthe second compressible element 262B may be less than the first springconstant of the first compressible element 262A. In embodiments, theuncompressed length of the second compressible element 262B may besimilar to the uncompressed length of the first compressible element262A. In other embodiments, the uncompressed length of the secondcompressible element 262B may be greater than the uncompressed length ofthe first compressible element 262A. In yet other embodiments, theuncompressed length of the second compressible element 262B may be lessthan the uncompressed length of the first compressible element 262A.

In embodiments, the second compressible element 262B includes a metallichelical coil spring having any number of turns. In embodiments, thesecond compressible element 262B includes a metallic helical coil springfabricated using one or more corrosion resistant material such as,aluminum, stainless steel, galvanized steel, coated steel, nickelcontaining alloys, titanium, or combinations thereof. The flexible shaft110 passes through a central aperture formed in the second compressibleelement 262B. In embodiments, the second compressible element 262B mayinclude a helical coil spring formed using round, square, or rectangularwire stock.

A first end of the third compressible element 262C seats inside a cavityor void space formed inside the third annular connector 270D and asecond end of the third compressible element 262C seats inside a cavityor void space formed inside a first end of the fourth annular connector270E. In embodiments, the first end of the third compressible element262C may be physically affixed inside the cavity or void space insidethe third annular connector 270C. In embodiments, the first end of thethird compressible element 262C may be press-fit, chemically bonded,and/or thermally welded inside the cavity or void space inside the thirdannular connector 270D. In other embodiments, the second end of thethird compressible element 262C may be detachably attached to the insidesurface of the cavity or void space inside the third annular connector270D. For example the first end of the third compressible element 262Cmay be threadedly attached to the inside surface of the cavity or voidspace inside the third annular connector 270D. The third annularconnector 270D may be positioned proximate the second cylindricalfloating spacer element 1820B. The fourth annular connector 270E may bepositioned proximate the coupling assembly 190.

The third compressible element 262C may include any number and/orcombination of metallic or non-metallic members capable of compressionalong the longitudinal axis 112 of the flexible member 110 uponapplication of a force applied along the longitudinal axis 112 of theflexible member 110. In embodiments, the third compressible element 262Cincludes a compressible element having a third spring constant (K₃)under compression. In embodiments, the third compressible element 262Cincludes a metallic helical coil spring having any number of turns. Inembodiments, the third compressible element 262C includes a metallichelical coil spring fabricated using one or more corrosion resistantmaterial such as, aluminum, stainless steel, galvanized steel, coatedsteel, nickel containing alloys, titanium, or combinations thereof. Theflexible shaft 110 passes through a central aperture formed in the thirdcompressible element 262C. The third compressible element 262C mayinclude a helical coil spring formed using round, square, or rectangularwire stock.

In embodiments, the third spring constant of the third compressibleelement 262C may be the same as or similar to the first spring constantof the first compressible element 262A and/or the second spring constantof the second compressible element 262B. In other embodiments, the thirdspring constant of the third compressible element 262C may be greaterthan the first spring constant of the first compressible element 262Aand/or the second spring constant of the second compressible element262B. In yet other embodiments, the third spring constant of the thirdcompressible element 262C may be less than the first spring constant ofthe first compressible element 262A and/or the second spring constant ofthe second compressible element 262B.

In embodiments, the uncompressed length of the third compressibleelement 262C may be the same as or similar to the uncompressed length ofthe first compressible element 262A and/or the uncompressed length ofthe second compressible element 262B. In other embodiments, theuncompressed length of the third compressible element 262C may begreater than the uncompressed length of the first compressible element262A and/or the uncompressed length of the second compressible element262B. In yet other embodiments, the uncompressed length of the thirdcompressible element 262C may be less than the uncompressed length ofthe first compressible element 262A and/or the uncompressed length ofthe second compressible element 262B.

FIG. 21 is a side elevation view of an illustrative pipelinereinstatement tool 2100 that includes: a flexible sleeve portion 140having a flexible member 242, an external flexible member 510 disposedabout at least a portion of the flexible member 242, and two cylindricalfloating spacer elements 1820A and 1820B disposed along the flexibleshaft 110 and positioned between a first compressible tensioner 160A anda second compressible tensioner 160B, in accordance with at least oneembodiment described herein. FIG. 21A is a sectional view of theillustrative pipeline reinstatement tool 2100 depicted in FIG. 21 alongsectional line 21A-21A, in accordance with at least one embodimentdescribed herein.

Referring first to FIGS. 21 and 21B, the flexible sleeve portion 140includes the flexible member 242 and a first external flexible member510 disposed about at least a portion of the first flexible member 242.In embodiments, the external flexible member 510 encircles at least aportion of the axial length of the flexible member 242. The externalflexible member 510 may enclose, encompass, or encircle about 10% orless; about 20% or less; about 30% or less; about 50% or less; or about75% or less of the axial length of the flexible member 242. Inembodiments, the flexible member 242 may include a tightly coiled springmember and the external flexible member 510 may include a tightly coiledspring member having an inside diameter that closely matches the outsidediameter of the flexible member 242. In such embodiments, the internalsurface of the external flexible member 510 may threadedly engage theexternal surface of the flexible member 242. As the flexible member 242is inserted into the external flexible member 510, the stiffness of theflexible sleeve portion 140 increases and as the flexible member 242 iswithdrawn from the external flexible member 510, the stiffness of theflexible sleeve 140 decreases.

The terms and expressions which have been employed herein are used asterms of description and not of limitation, and there is no intention,in the use of such terms and expressions, of excluding any equivalentsof the features shown and described (or portions thereof), and it isrecognized that various modifications are possible within the scope ofthe claims. Accordingly, the claims are intended to cover all suchequivalents. Various features, aspects, and embodiments have beendescribed herein. The features, aspects, and embodiments are susceptibleto combination with one another as well as to variation andmodification, as will be understood by those having skill in the art.The present disclosure should, therefore, be considered to encompasssuch combinations, variations, and modifications.

Reference throughout this specification to “one embodiment” or “anembodiment” means that a particular feature, structure, orcharacteristic described in connection with the embodiment is includedin at least one embodiment. Thus, appearances of the phrases “in oneembodiment” or “in an embodiment” in various places throughout thisspecification are not necessarily all referring to the same embodiment.Furthermore, the particular features, structures, or characteristics maybe combined in any suitable manner in one or more embodiments.

What is claimed is:
 1. A reinstatement tool, comprising: a flexibleshaft having a first length, a first end, and a second end; a cuttinghead coupled to the first end of the flexible shaft, the cutting headincluding: a hollow cylindrical member having a first end, a second end,an internal surface and an external surface; and cutting teeth disposedon a first end of the hollow cylindrical member and extendinglongitudinally from the first end of the hollow cylindrical member; acoupling assembly coupled to the second end of the flexible shaft; afirst compressible tensioner portion disposed around the flexible shaftand extending a first distance along the flexible shaft, the firstcompressible tensioner portion disposed proximate the cutting head, thefirst compressible tensioner including; first annular connector; anintermediate annular connector; a second annular connector; a firstcompressible element having a first spring constant disposed between thefirst annular connector and the intermediate annular connector; and asecond compressible element having a second spring constant disposedbetween the intermediate annular connector and the second annulareconnector a second compressible tensioner portion disposed around theflexible shaft and extending a second distance along the flexible shaft,the second compressible tensioner portion disposed proximate thecoupling assembly; and a flexible sleeve disposed around the flexibleshaft and positioned between the first compressible tensioner portionand the second compressible tensioner portion.
 2. The reinstatement toolof claim 1 wherein the first spring constant is similar to the secondspring constant.
 3. The reinstatement tool of claim 1 wherein the firstspring constant is greater than the second spring constant.
 4. Thereinstatement tool of claim 1 wherein the first spring constant is lessthan the second spring constant.
 5. The reinstatement tool of claim 1wherein the second compressible tensioner portion comprises: a thirdannular connector; a fourth annular connector; and a third compressibleelement having a third spring constant disposed between the thirdannular connector and the fourth annular connector.
 6. The reinstatementtool of claim 5 wherein the flexible sleeve comprises: a firstcylindrical floating spacer element disposed around the flexible shaft;a second cylindrical floating spacer element disposed around theflexible shaft; a flexible member disposed about the flexible shaft andpositioned between the first cylindrical floating spacer element and thesecond cylindrical floating spacer element.
 7. The reinstatement tool ofclaim 6, further comprising: an external flexible member disposed aboutat least a portion of an external surface of the flexible member.
 8. Thereinstatement tool of claim 7: wherein the flexible member includes atightly wound helical coil having a first length; wherein the externalflexible member includes a tightly wound helical coil having a secondlength; wherein at least a portion of an internal surface of theexternal flexible member threadedly engaged at least a portion of anexternal surface of the flexible member.
 9. The reinstatement tool ofclaim 8 wherein the first length is greater than the second length. 10.The reinstatement tool of claim 6 wherein the cutting head comprises: abutton removal feature disposed within the hollow cylindrical member andextending radially inward from the internal surface of the hollowcylindrical member.
 11. The reinstatement tool of claim 10 wherein thecutting head further comprises: a hemispherical floating spacer memberdisposed about at least a portion of the external surface of the hollowcylindrical member.
 12. A pipeline reinstatement system, comprising: adriver to provide a shaft output; a rotatable external drive shaft tocouple to the driver shaft output; a pipeline reinstatement tool thatincludes: a flexible shaft having a first length, a first end, and asecond end; a cutting head coupled to the first end of the flexibleshaft, the cutting head including: a hollow cylindrical member having afirst end, a second end, an internal surface and an external surface;and cutting teeth disposed on a first end of the hollow cylindricalmember and extending longitudinally from the first end of the hollowcylindrical member; a coupling assembly coupled to the second end of theflexible shaft, the coupling assembly to couple the flexible shaft tothe rotatable external drive shaft; a first compressible tensionerportion disposed around the flexible shaft and extending a firstdistance along the flexible shaft, the first compressible tensionerportion disposed proximate the cutting head, the first compressibletensioner including; a first annular connector; an intermediate annularconnector; a second annular connector; a first compressible elementhaving a first spring constant disposed between the first annularconnector and the intermediate annular connector; and a secondcompressible element having a second spring constant disposed betweenthe intermediate annular connector and the second annulare connector; asecond compressible tensioner portion disposed around the flexible shaftand extending a second distance along the flexible shaft, the secondcompressible tensioner portion disposed proximate the coupling assembly,the second compressible tensioner portion; and a flexible sleevedisposed around the flexible shaft and positioned between the firstcompressible tensioner portion and the second compressible tensionerportion.
 13. The system of claim 12 wherein the first spring constant issimilar to the second spring constant.
 14. The system of claim 12wherein the first spring constant is greater than the second springconstant.
 15. The system of claim 12 wherein the first spring constantis less than the second spring constant.
 16. The system of claim 12wherein the second compressible tensioner portion comprises: a thirdannular connector; a fourth annular connector; and a third compressibleelement having a third spring constant disposed between the thirdannular connector and the fourth annular connector.
 17. The system ofclaim 16 wherein the flexible sleeve portion comprises: a firstcylindrical floating spacer element disposed around the flexible shaft;a second cylindrical floating spacer element disposed around theflexible shaft; a flexible member disposed about the flexible shaft andpositioned between the first cylindrical floating spacer element and thesecond cylindrical floating spacer element.
 18. A reinstatement tool,comprising: a flexible shaft having a first length, a first end, and asecond end; a cutting head coupled to the first end of the flexibleshaft, the cutting head including: a hollow cylindrical member having afirst end, a second end, an internal surface and an external surface;cutting teeth disposed on a first end of the hollow cylindrical memberand extending longitudinally from the first end of the hollowcylindrical member; a button removal feature disposed within the hollowcylindrical member and extending radially inward from the internalsurface of the hollow cylindrical member; and a hemispherical floatingspacer member disposed about at least a portion of the external surfaceof the hollow cylindrical member; a coupling assembly coupled to thesecond end of the flexible shaft; a first compressible tensioner portiondisposed around the flexible shaft and extending a first distance alongthe flexible shaft, the first compressible tensioner portion disposedproximate the cutting head, the first compressible tensioner including:a first annular connector; an intermediate annular connector; a secondannular connector; a first compressible element having a first springconstant disposed between the first annular connector and theintermediate annular connector; and a second compressible element havinga second spring constant disposed between the intermediate annularconnector and the second annulare connector; a second compressibletensioner portion disposed around the flexible shaft and extending asecond distance along the flexible shaft, the second compressibletensioner portion disposed proximate the coupling assembly, the secondcompressible tensioner portion, the second compressible tensionerincluding: a third annular connector; a fourth annular connector; and athird compressible element having a third spring constant disposedbetween the third annular connector and the fourth annular connector;and a flexible sleeve disposed around the flexible shaft and positionedbetween the first compressible tensioner portion and the secondcompressible tensioner portion, the flexible sleeve including: a firstcylindrical floating spacer element disposed around the flexible shaft;a second cylindrical floating spacer element disposed around theflexible shaft; a flexible member disposed about the flexible shaft andpositioned between the first cylindrical floating spacer element and thesecond cylindrical floating spacer element.